Arc

Struct Arc 

1.0.0 · Source
pub struct Arc<T, A = Global>
where A: Allocator, T: ?Sized,
{ /* private fields */ }
Expand description

A thread-safe reference-counting pointer. ‘Arc’ stands for ‘Atomically Reference Counted’.

The type Arc<T> provides shared ownership of a value of type T, allocated in the heap. Invoking clone on Arc produces a new Arc instance, which points to the same allocation on the heap as the source Arc, while increasing a reference count. When the last Arc pointer to a given allocation is destroyed, the value stored in that allocation (often referred to as “inner value”) is also dropped.

Shared references in Rust disallow mutation by default, and Arc is no exception: you cannot generally obtain a mutable reference to something inside an Arc. If you do need to mutate through an Arc, you have several options:

  1. Use interior mutability with synchronization primitives like Mutex, RwLock, or one of the Atomic types.

  2. Use clone-on-write semantics with Arc::make_mut which provides efficient mutation without requiring interior mutability. This approach clones the data only when needed (when there are multiple references) and can be more efficient when mutations are infrequent.

  3. Use Arc::get_mut when you know your Arc is not shared (has a reference count of 1), which provides direct mutable access to the inner value without any cloning.

use std::sync::Arc;

let mut data = Arc::new(vec![1, 2, 3]);

// This will clone the vector only if there are other references to it
Arc::make_mut(&mut data).push(4);

assert_eq!(*data, vec![1, 2, 3, 4]);

Note: This type is only available on platforms that support atomic loads and stores of pointers, which includes all platforms that support the std crate but not all those which only support alloc. This may be detected at compile time using #[cfg(target_has_atomic = "ptr")].

§Thread Safety

Unlike Rc<T>, Arc<T> uses atomic operations for its reference counting. This means that it is thread-safe. The disadvantage is that atomic operations are more expensive than ordinary memory accesses. If you are not sharing reference-counted allocations between threads, consider using Rc<T> for lower overhead. Rc<T> is a safe default, because the compiler will catch any attempt to send an Rc<T> between threads. However, a library might choose Arc<T> in order to give library consumers more flexibility.

Arc<T> will implement Send and Sync as long as the T implements Send and Sync. Why can’t you put a non-thread-safe type T in an Arc<T> to make it thread-safe? This may be a bit counter-intuitive at first: after all, isn’t the point of Arc<T> thread safety? The key is this: Arc<T> makes it thread safe to have multiple ownership of the same data, but it doesn’t add thread safety to its data. Consider Arc<RefCell<T>>. RefCell<T> isn’t Sync, and if Arc<T> was always Send, Arc<RefCell<T>> would be as well. But then we’d have a problem: RefCell<T> is not thread safe; it keeps track of the borrowing count using non-atomic operations.

In the end, this means that you may need to pair Arc<T> with some sort of std::sync type, usually Mutex<T>.

§Breaking cycles with Weak

The downgrade method can be used to create a non-owning Weak pointer. A Weak pointer can be upgraded to an Arc, but this will return None if the value stored in the allocation has already been dropped. In other words, Weak pointers do not keep the value inside the allocation alive; however, they do keep the allocation (the backing store for the value) alive.

A cycle between Arc pointers will never be deallocated. For this reason, Weak is used to break cycles. For example, a tree could have strong Arc pointers from parent nodes to children, and Weak pointers from children back to their parents.

§Cloning references

Creating a new reference from an existing reference-counted pointer is done using the Clone trait implemented for Arc<T> and Weak<T>.

use std::sync::Arc;
let foo = Arc::new(vec![1.0, 2.0, 3.0]);
// The two syntaxes below are equivalent.
let a = foo.clone();
let b = Arc::clone(&foo);
// a, b, and foo are all Arcs that point to the same memory location

§Deref behavior

Arc<T> automatically dereferences to T (via the Deref trait), so you can call T’s methods on a value of type Arc<T>. To avoid name clashes with T’s methods, the methods of Arc<T> itself are associated functions, called using fully qualified syntax:

use std::sync::Arc;

let my_arc = Arc::new(());
let my_weak = Arc::downgrade(&my_arc);

Arc<T>’s implementations of traits like Clone may also be called using fully qualified syntax. Some people prefer to use fully qualified syntax, while others prefer using method-call syntax.

use std::sync::Arc;

let arc = Arc::new(());
// Method-call syntax
let arc2 = arc.clone();
// Fully qualified syntax
let arc3 = Arc::clone(&arc);

Weak<T> does not auto-dereference to T, because the inner value may have already been dropped.

§Examples

Sharing some immutable data between threads:

use std::sync::Arc;
use std::thread;

let five = Arc::new(5);

for _ in 0..10 {
    let five = Arc::clone(&five);

    thread::spawn(move || {
        println!("{five:?}");
    });
}

Sharing a mutable AtomicUsize:

use std::sync::Arc;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::thread;

let val = Arc::new(AtomicUsize::new(5));

for _ in 0..10 {
    let val = Arc::clone(&val);

    thread::spawn(move || {
        let v = val.fetch_add(1, Ordering::Relaxed);
        println!("{v:?}");
    });
}

See the rc documentation for more examples of reference counting in general.

Implementations§

Source§

impl<T> Arc<T>

1.0.0 · Source

pub fn new(data: T) -> Arc<T>

Constructs a new Arc<T>.

§Examples
use std::sync::Arc;

let five = Arc::new(5);
Examples found in repository?
examples/03_geo_analysis/stationkeeping.rs (line 31)
28fn main() -> Result<(), Box<dyn Error>> {
29    pel::init();
30    // Set up the dynamics like in the orbit raise.
31    let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
32    let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
33
34    // Define the GEO orbit, and we're just going to maintain it very tightly.
35    let earth_j2000 = almanac.frame_from_uid(EARTH_J2000)?;
36    let orbit = Orbit::try_keplerian(42164.0, 1e-5, 0., 163.0, 75.0, 0.0, epoch, earth_j2000)?;
37    println!("{orbit:x}");
38
39    let sc = Spacecraft::builder()
40        .orbit(orbit)
41        .mass(Mass::from_dry_and_prop_masses(1000.0, 1000.0)) // 1000 kg of dry mass and prop, totalling 2.0 tons
42        .srp(SRPData::from_area(3.0 * 6.0)) // Assuming 1 kW/m^2 or 18 kW, giving a margin of 4.35 kW for on-propulsion consumption
43        .thruster(Thruster {
44            // "NEXT-STEP" row in Table 2
45            isp_s: 4435.0,
46            thrust_N: 0.472,
47        })
48        .mode(GuidanceMode::Thrust) // Start thrusting immediately.
49        .build();
50
51    // Set up the spacecraft dynamics like in the orbit raise example.
52
53    let prop_time = 30.0 * Unit::Day;
54
55    // Define the guidance law -- we're just using a Ruggiero controller as demonstrated in AAS-2004-5089.
56    let objectives = &[
57        Objective::within_tolerance(StateParameter::SMA, 42_164.0, 5.0), // 5 km
58        Objective::within_tolerance(StateParameter::Eccentricity, 0.001, 5e-5),
59        Objective::within_tolerance(StateParameter::Inclination, 0.05, 1e-2),
60    ];
61
62    let ruggiero_ctrl = Ruggiero::from_max_eclipse(objectives, sc, 0.2)?;
63    println!("{ruggiero_ctrl}");
64
65    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
66
67    let mut jgm3_meta = MetaFile {
68        uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
69        crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
70    };
71    jgm3_meta.process(true)?;
72
73    let harmonics = Harmonics::from_stor(
74        almanac.frame_from_uid(IAU_EARTH_FRAME)?,
75        HarmonicsMem::from_cof(&jgm3_meta.uri, 8, 8, true)?,
76    );
77    orbital_dyn.accel_models.push(harmonics);
78
79    let srp_dyn = SolarPressure::default(EARTH_J2000, almanac.clone())?;
80    let sc_dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn)
81        .with_guidance_law(ruggiero_ctrl.clone());
82
83    println!("{sc_dynamics}");
84
85    // Finally, let's use the Monte Carlo framework built into Nyx to propagate spacecraft.
86
87    // Let's start by defining the dispersion.
88    // The MultivariateNormal structure allows us to define the dispersions in any of the orbital parameters, but these are applied directly in the Cartesian state space.
89    // Note that additional validation on the MVN is in progress -- https://github.com/nyx-space/nyx/issues/339.
90    let mc_rv = MvnSpacecraft::new(
91        sc,
92        vec![StateDispersion::zero_mean(StateParameter::SMA, 3.0)],
93    )?;
94
95    let my_mc = MonteCarlo::new(
96        sc, // Nominal state
97        mc_rv,
98        "03_geo_sk".to_string(), // Scenario name
99        None, // No specific seed specified, so one will be drawn from the computer's entropy.
100    );
101
102    // Build the propagator setup.
103    let setup = Propagator::rk89(
104        sc_dynamics.clone(),
105        IntegratorOptions::builder()
106            .min_step(10.0_f64.seconds())
107            .error_ctrl(ErrorControl::RSSCartesianStep)
108            .build(),
109    );
110
111    let num_runs = 25;
112    let rslts = my_mc.run_until_epoch(setup, almanac.clone(), sc.epoch() + prop_time, num_runs);
113
114    assert_eq!(rslts.runs.len(), num_runs);
115
116    // For all of the resulting trajectories, we'll want to compute the percentage of penumbra and umbra.
117
118    rslts.to_parquet(
119        "03_geo_sk.parquet",
120        Some(vec![
121            &EclipseLocator::cislunar(almanac.clone()).to_penumbra_event()
122        ]),
123        ExportCfg::default(),
124        almanac,
125    )?;
126
127    Ok(())
128}
More examples
Hide additional examples
examples/03_geo_analysis/raise.rs (line 39)
27fn main() -> Result<(), Box<dyn Error>> {
28    pel::init();
29
30    // Dynamics models require planetary constants and ephemerides to be defined.
31    // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
32    // This will automatically download the DE440s planetary ephemeris,
33    // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
34    // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
35    // planetary constants kernels.
36    // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
37    // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
38    // references to many functions.
39    let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
40    // Fetch the EME2000 frame from the Almabac
41    let eme2k = almanac.frame_from_uid(EARTH_J2000).unwrap();
42    // Define the orbit epoch
43    let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
44
45    // Build the spacecraft itself.
46    // Using slide 6 of https://aerospace.org/sites/default/files/2018-11/Davis-Mayberry_HPSEP_11212018.pdf
47    // for the "next gen" SEP characteristics.
48
49    // GTO start
50    let orbit = Orbit::keplerian(24505.9, 0.725, 7.05, 0.0, 0.0, 0.0, epoch, eme2k);
51
52    let sc = Spacecraft::builder()
53        .orbit(orbit)
54        .mass(Mass::from_dry_and_prop_masses(1000.0, 1000.0)) // 1000 kg of dry mass and prop, totalling 2.0 tons
55        .srp(SRPData::from_area(3.0 * 6.0)) // Assuming 1 kW/m^2 or 18 kW, giving a margin of 4.35 kW for on-propulsion consumption
56        .thruster(Thruster {
57            // "NEXT-STEP" row in Table 2
58            isp_s: 4435.0,
59            thrust_N: 0.472,
60        })
61        .mode(GuidanceMode::Thrust) // Start thrusting immediately.
62        .build();
63
64    let prop_time = 180.0 * Unit::Day;
65
66    // Define the guidance law -- we're just using a Ruggiero controller as demonstrated in AAS-2004-5089.
67    let objectives = &[
68        Objective::within_tolerance(StateParameter::SMA, 42_165.0, 20.0),
69        Objective::within_tolerance(StateParameter::Eccentricity, 0.001, 5e-5),
70        Objective::within_tolerance(StateParameter::Inclination, 0.05, 1e-2),
71    ];
72
73    // Ensure that we only thrust if we have more than 20% illumination.
74    let ruggiero_ctrl = Ruggiero::from_max_eclipse(objectives, sc, 0.2).unwrap();
75    println!("{ruggiero_ctrl}");
76
77    // Define the high fidelity dynamics
78
79    // Set up the spacecraft dynamics.
80
81    // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
82    // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
83    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
84
85    // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
86    // We're using the JGM3 model here, which is the default in GMAT.
87    let mut jgm3_meta = MetaFile {
88        uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
89        crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
90    };
91    // And let's download it if we don't have it yet.
92    jgm3_meta.process(true)?;
93
94    // Build the spherical harmonics.
95    // The harmonics must be computed in the body fixed frame.
96    // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
97    let harmonics = Harmonics::from_stor(
98        almanac.frame_from_uid(IAU_EARTH_FRAME)?,
99        HarmonicsMem::from_cof(&jgm3_meta.uri, 8, 8, true).unwrap(),
100    );
101
102    // Include the spherical harmonics into the orbital dynamics.
103    orbital_dyn.accel_models.push(harmonics);
104
105    // We define the solar radiation pressure, using the default solar flux and accounting only
106    // for the eclipsing caused by the Earth.
107    let srp_dyn = SolarPressure::default(EARTH_J2000, almanac.clone())?;
108
109    // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
110    // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
111    let sc_dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn)
112        .with_guidance_law(ruggiero_ctrl.clone());
113
114    println!("{orbit:x}");
115
116    // We specify a minimum step in the propagator because the Ruggiero control would otherwise drive this step very low.
117    let (final_state, traj) = Propagator::rk89(
118        sc_dynamics.clone(),
119        IntegratorOptions::builder()
120            .min_step(10.0_f64.seconds())
121            .error_ctrl(ErrorControl::RSSCartesianStep)
122            .build(),
123    )
124    .with(sc, almanac.clone())
125    .for_duration_with_traj(prop_time)?;
126
127    let prop_usage = sc.mass.prop_mass_kg - final_state.mass.prop_mass_kg;
128    println!("{:x}", final_state.orbit);
129    println!("prop usage: {prop_usage:.3} kg");
130
131    // Finally, export the results for analysis, including the penumbra percentage throughout the orbit raise.
132    traj.to_parquet(
133        "./03_geo_raise.parquet",
134        Some(vec![
135            &EclipseLocator::cislunar(almanac.clone()).to_penumbra_event()
136        ]),
137        ExportCfg::default(),
138        almanac,
139    )?;
140
141    for status_line in ruggiero_ctrl.status(&final_state) {
142        println!("{status_line}");
143    }
144
145    ruggiero_ctrl
146        .achieved(&final_state)
147        .expect("objective not achieved");
148
149    Ok(())
150}
examples/02_jwst_covar_monte_carlo/main.rs (lines 41-45)
26fn main() -> Result<(), Box<dyn Error>> {
27    pel::init();
28    // Dynamics models require planetary constants and ephemerides to be defined.
29    // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
30    // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
31
32    // Download the regularly update of the James Webb Space Telescope reconstucted (or definitive) ephemeris.
33    // Refer to https://naif.jpl.nasa.gov/pub/naif/JWST/kernels/spk/aareadme.txt for details.
34    let mut latest_jwst_ephem = MetaFile {
35        uri: "https://naif.jpl.nasa.gov/pub/naif/JWST/kernels/spk/jwst_rec.bsp".to_string(),
36        crc32: None,
37    };
38    latest_jwst_ephem.process(true)?;
39
40    // Load this ephem in the general Almanac we're using for this analysis.
41    let almanac = Arc::new(
42        MetaAlmanac::latest()
43            .map_err(Box::new)?
44            .load_from_metafile(latest_jwst_ephem, true)?,
45    );
46
47    // By loading this ephemeris file in the ANISE GUI or ANISE CLI, we can find the NAIF ID of the JWST
48    // in the BSP. We need this ID in order to query the ephemeris.
49    const JWST_NAIF_ID: i32 = -170;
50    // Let's build a frame in the J2000 orientation centered on the JWST.
51    const JWST_J2000: Frame = Frame::from_ephem_j2000(JWST_NAIF_ID);
52
53    // Since the ephemeris file is updated regularly, we'll just grab the latest state in the ephem.
54    let (earliest_epoch, latest_epoch) = almanac.spk_domain(JWST_NAIF_ID)?;
55    println!("JWST defined from {earliest_epoch} to {latest_epoch}");
56    // Fetch the state, printing it in the Earth J2000 frame.
57    let jwst_orbit = almanac.transform(JWST_J2000, EARTH_J2000, latest_epoch, None)?;
58    println!("{jwst_orbit:x}");
59
60    // Build the spacecraft
61    // SRP area assumed to be the full sunshield and mass if 6200.0 kg, c.f. https://webb.nasa.gov/content/about/faqs/facts.html
62    // SRP Coefficient of reflectivity assumed to be that of Kapton, i.e. 2 - 0.44 = 1.56, table 1 from https://amostech.com/TechnicalPapers/2018/Poster/Bengtson.pdf
63    let jwst = Spacecraft::builder()
64        .orbit(jwst_orbit)
65        .srp(SRPData {
66            area_m2: 21.197 * 14.162,
67            coeff_reflectivity: 1.56,
68        })
69        .mass(Mass::from_dry_mass(6200.0))
70        .build();
71
72    // Build up the spacecraft uncertainty builder.
73    // We can use the spacecraft uncertainty structure to build this up.
74    // We start by specifying the nominal state (as defined above), then the uncertainty in position and velocity
75    // in the RIC frame. We could also specify the Cr, Cd, and mass uncertainties, but these aren't accounted for until
76    // Nyx can also estimate the deviation of the spacecraft parameters.
77    let jwst_uncertainty = SpacecraftUncertainty::builder()
78        .nominal(jwst)
79        .frame(LocalFrame::RIC)
80        .x_km(0.5)
81        .y_km(0.3)
82        .z_km(1.5)
83        .vx_km_s(1e-4)
84        .vy_km_s(0.6e-3)
85        .vz_km_s(3e-3)
86        .build();
87
88    println!("{jwst_uncertainty}");
89
90    // Build the Kalman filter estimate.
91    // Note that we could have used the KfEstimate structure directly (as seen throughout the OD integration tests)
92    // but this approach requires quite a bit more boilerplate code.
93    let jwst_estimate = jwst_uncertainty.to_estimate()?;
94
95    // Set up the spacecraft dynamics.
96    // We'll use the point masses of the Earth, Sun, Jupiter (barycenter, because it's in the DE440), and the Moon.
97    // We'll also enable solar radiation pressure since the James Webb has a huge and highly reflective sun shield.
98
99    let orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN, JUPITER_BARYCENTER]);
100    let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], almanac.clone())?;
101
102    // Finalize setting up the dynamics.
103    let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
104
105    // Build the propagator set up to use for the whole analysis.
106    let setup = Propagator::default(dynamics);
107
108    // All of the analysis will use this duration.
109    let prediction_duration = 6.5 * Unit::Day;
110
111    // === Covariance mapping ===
112    // For the covariance mapping / prediction, we'll use the common orbit determination approach.
113    // This is done by setting up a spacecraft Kalman filter OD process, and predicting for the analysis duration.
114
115    // Build the propagation instance for the OD process.
116    let odp = SpacecraftKalmanOD::new(
117        setup.clone(),
118        KalmanVariant::DeviationTracking,
119        None,
120        BTreeMap::new(),
121        almanac.clone(),
122    );
123
124    // The prediction step is 1 minute by default, configured in the OD process, i.e. how often we want to know the covariance.
125    assert_eq!(odp.max_step, 1_i64.minutes());
126    // Finally, predict, and export the trajectory with covariance to a parquet file.
127    let od_sol = odp.predict_for(jwst_estimate, prediction_duration)?;
128    od_sol.to_parquet("./02_jwst_covar_map.parquet", ExportCfg::default())?;
129
130    // === Monte Carlo framework ===
131    // Nyx comes with a complete multi-threaded Monte Carlo frame. It's blazing fast.
132
133    let my_mc = MonteCarlo::new(
134        jwst, // Nominal state
135        jwst_estimate.to_random_variable()?,
136        "02_jwst".to_string(), // Scenario name
137        None, // No specific seed specified, so one will be drawn from the computer's entropy.
138    );
139
140    let num_runs = 5_000;
141    let rslts = my_mc.run_until_epoch(
142        setup,
143        almanac.clone(),
144        jwst.epoch() + prediction_duration,
145        num_runs,
146    );
147
148    assert_eq!(rslts.runs.len(), num_runs);
149    // Finally, export these results, computing the eclipse percentage for all of these results.
150
151    // For all of the resulting trajectories, we'll want to compute the percentage of penumbra and umbra.
152    let eclipse_loc = EclipseLocator::cislunar(almanac.clone());
153    let umbra_event = eclipse_loc.to_umbra_event();
154    let penumbra_event = eclipse_loc.to_penumbra_event();
155
156    rslts.to_parquet(
157        "02_jwst_monte_carlo.parquet",
158        Some(vec![&umbra_event, &penumbra_event]),
159        ExportCfg::default(),
160        almanac,
161    )?;
162
163    Ok(())
164}
examples/03_geo_analysis/drift.rs (line 37)
26fn main() -> Result<(), Box<dyn Error>> {
27    pel::init();
28    // Dynamics models require planetary constants and ephemerides to be defined.
29    // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
30    // This will automatically download the DE440s planetary ephemeris,
31    // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
32    // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
33    // planetary constants kernels.
34    // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
35    // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
36    // references to many functions.
37    let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
38    // Define the orbit epoch
39    let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
40
41    // Define the orbit.
42    // First we need to fetch the Earth J2000 from information from the Almanac.
43    // This allows the frame to include the gravitational parameters and the shape of the Earth,
44    // defined as a tri-axial ellipoid. Note that this shape can be changed manually or in the Almanac
45    // by loading a different set of planetary constants.
46    let earth_j2000 = almanac.frame_from_uid(EARTH_J2000)?;
47
48    // Placing this GEO bird just above Colorado.
49    // In theory, the eccentricity is zero, but in practice, it's about 1e-5 to 1e-6 at best.
50    let orbit = Orbit::try_keplerian(42164.0, 1e-5, 0., 163.0, 75.0, 0.0, epoch, earth_j2000)?;
51    // Print in in Keplerian form.
52    println!("{orbit:x}");
53
54    let state_bf = almanac.transform_to(orbit, IAU_EARTH_FRAME, None)?;
55    let (orig_lat_deg, orig_long_deg, orig_alt_km) = state_bf.latlongalt()?;
56
57    // Nyx is used for high fidelity propagation, not Keplerian propagation as above.
58    // Nyx only propagates Spacecraft at the moment, which allows it to account for acceleration
59    // models such as solar radiation pressure.
60
61    // Let's build a cubesat sized spacecraft, with an SRP area of 10 cm^2 and a mass of 9.6 kg.
62    let sc = Spacecraft::builder()
63        .orbit(orbit)
64        .mass(Mass::from_dry_mass(9.60))
65        .srp(SRPData {
66            area_m2: 10e-4,
67            coeff_reflectivity: 1.1,
68        })
69        .build();
70    println!("{sc:x}");
71
72    // Set up the spacecraft dynamics.
73
74    // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
75    // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
76    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
77
78    // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
79    // We're using the JGM3 model here, which is the default in GMAT.
80    let mut jgm3_meta = MetaFile {
81        uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
82        crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
83    };
84    // And let's download it if we don't have it yet.
85    jgm3_meta.process(true)?;
86
87    // Build the spherical harmonics.
88    // The harmonics must be computed in the body fixed frame.
89    // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
90    let harmonics_21x21 = Harmonics::from_stor(
91        almanac.frame_from_uid(IAU_EARTH_FRAME)?,
92        HarmonicsMem::from_cof(&jgm3_meta.uri, 21, 21, true).unwrap(),
93    );
94
95    // Include the spherical harmonics into the orbital dynamics.
96    orbital_dyn.accel_models.push(harmonics_21x21);
97
98    // We define the solar radiation pressure, using the default solar flux and accounting only
99    // for the eclipsing caused by the Earth and Moon.
100    let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], almanac.clone())?;
101
102    // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
103    // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
104    let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
105
106    println!("{dynamics}");
107
108    // Finally, let's propagate this orbit to the same epoch as above.
109    // The first returned value is the spacecraft state at the final epoch.
110    // The second value is the full trajectory where the step size is variable step used by the propagator.
111    let (future_sc, trajectory) = Propagator::default(dynamics)
112        .with(sc, almanac.clone())
113        .until_epoch_with_traj(epoch + Unit::Century * 0.03)?;
114
115    println!("=== High fidelity propagation ===");
116    println!(
117        "SMA changed by {:.3} km",
118        orbit.sma_km()? - future_sc.orbit.sma_km()?
119    );
120    println!(
121        "ECC changed by {:.6}",
122        orbit.ecc()? - future_sc.orbit.ecc()?
123    );
124    println!(
125        "INC changed by {:.3e} deg",
126        orbit.inc_deg()? - future_sc.orbit.inc_deg()?
127    );
128    println!(
129        "RAAN changed by {:.3} deg",
130        orbit.raan_deg()? - future_sc.orbit.raan_deg()?
131    );
132    println!(
133        "AOP changed by {:.3} deg",
134        orbit.aop_deg()? - future_sc.orbit.aop_deg()?
135    );
136    println!(
137        "TA changed by {:.3} deg",
138        orbit.ta_deg()? - future_sc.orbit.ta_deg()?
139    );
140
141    // We also have access to the full trajectory throughout the propagation.
142    println!("{trajectory}");
143
144    println!("Spacecraft params after 3 years without active control:\n{future_sc:x}");
145
146    // With the trajectory, let's build a few data products.
147
148    // 1. Export the trajectory as a parquet file, which includes the Keplerian orbital elements.
149
150    let analysis_step = Unit::Minute * 5;
151
152    trajectory.to_parquet(
153        "./03_geo_hf_prop.parquet",
154        Some(vec![
155            &EclipseLocator::cislunar(almanac.clone()).to_penumbra_event()
156        ]),
157        ExportCfg::builder().step(analysis_step).build(),
158        almanac.clone(),
159    )?;
160
161    // 2. Compute the latitude, longitude, and altitude throughout the trajectory by rotating the spacecraft position into the Earth body fixed frame.
162
163    // We iterate over the trajectory, grabbing a state every two minutes.
164    let mut offset_s = vec![];
165    let mut epoch_str = vec![];
166    let mut longitude_deg = vec![];
167    let mut latitude_deg = vec![];
168    let mut altitude_km = vec![];
169
170    for state in trajectory.every(analysis_step) {
171        // Convert the GEO bird state into the body fixed frame, and keep track of its latitude, longitude, and altitude.
172        // These define the GEO stationkeeping box.
173
174        let this_epoch = state.epoch();
175
176        offset_s.push((this_epoch - orbit.epoch).to_seconds());
177        epoch_str.push(this_epoch.to_isoformat());
178
179        let state_bf = almanac.transform_to(state.orbit, IAU_EARTH_FRAME, None)?;
180        let (lat_deg, long_deg, alt_km) = state_bf.latlongalt()?;
181        longitude_deg.push(long_deg);
182        latitude_deg.push(lat_deg);
183        altitude_km.push(alt_km);
184    }
185
186    println!(
187        "Longitude changed by {:.3} deg -- Box is 0.1 deg E-W",
188        orig_long_deg - longitude_deg.last().unwrap()
189    );
190
191    println!(
192        "Latitude changed by {:.3} deg -- Box is 0.05 deg N-S",
193        orig_lat_deg - latitude_deg.last().unwrap()
194    );
195
196    println!(
197        "Altitude changed by {:.3} km -- Box is 30 km",
198        orig_alt_km - altitude_km.last().unwrap()
199    );
200
201    // Build the station keeping data frame.
202    let mut sk_df = df!(
203        "Offset (s)" => offset_s.clone(),
204        "Epoch (UTC)" => epoch_str.clone(),
205        "Longitude E-W (deg)" => longitude_deg,
206        "Latitude N-S (deg)" => latitude_deg,
207        "Altitude (km)" => altitude_km,
208
209    )?;
210
211    // Create a file to write the Parquet to
212    let file = File::create("./03_geo_lla.parquet").expect("Could not create file");
213
214    // Create a ParquetWriter and write the DataFrame to the file
215    ParquetWriter::new(file).finish(&mut sk_df)?;
216
217    Ok(())
218}
examples/04_lro_od/main.rs (line 70)
33fn main() -> Result<(), Box<dyn Error>> {
34    pel::init();
35
36    // ====================== //
37    // === ALMANAC SET UP === //
38    // ====================== //
39
40    // Dynamics models require planetary constants and ephemerides to be defined.
41    // Let's start by grabbing those by using ANISE's MetaAlmanac.
42
43    let data_folder: PathBuf = [env!("CARGO_MANIFEST_DIR"), "examples", "04_lro_od"]
44        .iter()
45        .collect();
46
47    let meta = data_folder.join("lro-dynamics.dhall");
48
49    // Load this ephem in the general Almanac we're using for this analysis.
50    let mut almanac = MetaAlmanac::new(meta.to_string_lossy().to_string())
51        .map_err(Box::new)?
52        .process(true)
53        .map_err(Box::new)?;
54
55    let mut moon_pc = almanac.planetary_data.get_by_id(MOON)?;
56    moon_pc.mu_km3_s2 = 4902.74987;
57    almanac.planetary_data.set_by_id(MOON, moon_pc)?;
58
59    let mut earth_pc = almanac.planetary_data.get_by_id(EARTH)?;
60    earth_pc.mu_km3_s2 = 398600.436;
61    almanac.planetary_data.set_by_id(EARTH, earth_pc)?;
62
63    // Save this new kernel for reuse.
64    // In an operational context, this would be part of the "Lock" process, and should not change throughout the mission.
65    almanac
66        .planetary_data
67        .save_as(&data_folder.join("lro-specific.pca"), true)?;
68
69    // Lock the almanac (an Arc is a read only structure).
70    let almanac = Arc::new(almanac);
71
72    // Orbit determination requires a Trajectory structure, which can be saved as parquet file.
73    // In our case, the trajectory comes from the BSP file, so we need to build a Trajectory from the almanac directly.
74    // To query the Almanac, we need to build the LRO frame in the J2000 orientation in our case.
75    // Inspecting the LRO BSP in the ANISE GUI shows us that NASA has assigned ID -85 to LRO.
76    let lro_frame = Frame::from_ephem_j2000(-85);
77
78    // To build the trajectory we need to provide a spacecraft template.
79    let sc_template = Spacecraft::builder()
80        .mass(Mass::from_dry_and_prop_masses(1018.0, 900.0)) // Launch masses
81        .srp(SRPData {
82            // SRP configuration is arbitrary, but we will be estimating it anyway.
83            area_m2: 3.9 * 2.7,
84            coeff_reflectivity: 0.96,
85        })
86        .orbit(Orbit::zero(MOON_J2000)) // Setting a zero orbit here because it's just a template
87        .build();
88    // Now we can build the trajectory from the BSP file.
89    // We'll arbitrarily set the tracking arc to 24 hours with a five second time step.
90    let traj_as_flown = Traj::from_bsp(
91        lro_frame,
92        MOON_J2000,
93        almanac.clone(),
94        sc_template,
95        5.seconds(),
96        Some(Epoch::from_str("2024-01-01 00:00:00 UTC")?),
97        Some(Epoch::from_str("2024-01-02 00:00:00 UTC")?),
98        Aberration::LT,
99        Some("LRO".to_string()),
100    )?;
101
102    println!("{traj_as_flown}");
103
104    // ====================== //
105    // === MODEL MATCHING === //
106    // ====================== //
107
108    // Set up the spacecraft dynamics.
109
110    // Specify that the orbital dynamics must account for the graviational pull of the Earth and the Sun.
111    // The gravity of the Moon will also be accounted for since the spaceraft in a lunar orbit.
112    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![EARTH, SUN, JUPITER_BARYCENTER]);
113
114    // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
115    // We're using the GRAIL JGGRX model.
116    let mut jggrx_meta = MetaFile {
117        uri: "http://public-data.nyxspace.com/nyx/models/Luna_jggrx_1500e_sha.tab.gz".to_string(),
118        crc32: Some(0x6bcacda8), // Specifying the CRC32 avoids redownloading it if it's cached.
119    };
120    // And let's download it if we don't have it yet.
121    jggrx_meta.process(true)?;
122
123    // Build the spherical harmonics.
124    // The harmonics must be computed in the body fixed frame.
125    // We're using the long term prediction of the Moon principal axes frame.
126    let moon_pa_frame = MOON_PA_FRAME.with_orient(31008);
127    let sph_harmonics = Harmonics::from_stor(
128        almanac.frame_from_uid(moon_pa_frame)?,
129        HarmonicsMem::from_shadr(&jggrx_meta.uri, 80, 80, true)?,
130    );
131
132    // Include the spherical harmonics into the orbital dynamics.
133    orbital_dyn.accel_models.push(sph_harmonics);
134
135    // We define the solar radiation pressure, using the default solar flux and accounting only
136    // for the eclipsing caused by the Earth and Moon.
137    // Note that by default, enabling the SolarPressure model will also enable the estimation of the coefficient of reflectivity.
138    let srp_dyn = SolarPressure::new(vec![EARTH_J2000, MOON_J2000], almanac.clone())?;
139
140    // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
141    // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
142    let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
143
144    println!("{dynamics}");
145
146    // Now we can build the propagator.
147    let setup = Propagator::default_dp78(dynamics.clone());
148
149    // For reference, let's build the trajectory with Nyx's models from that LRO state.
150    let (sim_final, traj_as_sim) = setup
151        .with(*traj_as_flown.first(), almanac.clone())
152        .until_epoch_with_traj(traj_as_flown.last().epoch())?;
153
154    println!("SIM INIT:  {:x}", traj_as_flown.first());
155    println!("SIM FINAL: {sim_final:x}");
156    // Compute RIC difference between SIM and LRO ephem
157    let sim_lro_delta = sim_final
158        .orbit
159        .ric_difference(&traj_as_flown.last().orbit)?;
160    println!("{traj_as_sim}");
161    println!(
162        "SIM v LRO - RIC Position (m): {:.3}",
163        sim_lro_delta.radius_km * 1e3
164    );
165    println!(
166        "SIM v LRO - RIC Velocity (m/s): {:.3}",
167        sim_lro_delta.velocity_km_s * 1e3
168    );
169
170    traj_as_sim.ric_diff_to_parquet(
171        &traj_as_flown,
172        "./04_lro_sim_truth_error.parquet",
173        ExportCfg::default(),
174    )?;
175
176    // ==================== //
177    // === OD SIMULATOR === //
178    // ==================== //
179
180    // After quite some time trying to exactly match the model, we still end up with an oscillatory difference on the order of 150 meters between the propagated state
181    // and the truth LRO state.
182
183    // Therefore, we will actually run an estimation from a dispersed LRO state.
184    // The sc_seed is the true LRO state from the BSP.
185    let sc_seed = *traj_as_flown.first();
186
187    // Load the Deep Space Network ground stations.
188    // Nyx allows you to build these at runtime but it's pretty static so we can just load them from YAML.
189    let ground_station_file: PathBuf = [
190        env!("CARGO_MANIFEST_DIR"),
191        "examples",
192        "04_lro_od",
193        "dsn-network.yaml",
194    ]
195    .iter()
196    .collect();
197
198    let devices = GroundStation::load_named(ground_station_file)?;
199
200    // Typical OD software requires that you specify your own tracking schedule or you'll have overlapping measurements.
201    // Nyx can build a tracking schedule for you based on the first station with access.
202    let trkconfg_yaml: PathBuf = [
203        env!("CARGO_MANIFEST_DIR"),
204        "examples",
205        "04_lro_od",
206        "tracking-cfg.yaml",
207    ]
208    .iter()
209    .collect();
210
211    let configs: BTreeMap<String, TrkConfig> = TrkConfig::load_named(trkconfg_yaml)?;
212
213    // Build the tracking arc simulation to generate a "standard measurement".
214    let mut trk = TrackingArcSim::<Spacecraft, GroundStation>::new(
215        devices.clone(),
216        traj_as_flown.clone(),
217        configs,
218    )?;
219
220    trk.build_schedule(almanac.clone())?;
221    let arc = trk.generate_measurements(almanac.clone())?;
222    // Save the simulated tracking data
223    arc.to_parquet_simple("./04_lro_simulated_tracking.parquet")?;
224
225    // We'll note that in our case, we have continuous coverage of LRO when the vehicle is not behind the Moon.
226    println!("{arc}");
227
228    // Now that we have simulated measurements, we'll run the orbit determination.
229
230    // ===================== //
231    // === OD ESTIMATION === //
232    // ===================== //
233
234    let sc = SpacecraftUncertainty::builder()
235        .nominal(sc_seed)
236        .frame(LocalFrame::RIC)
237        .x_km(0.5)
238        .y_km(0.5)
239        .z_km(0.5)
240        .vx_km_s(5e-3)
241        .vy_km_s(5e-3)
242        .vz_km_s(5e-3)
243        .build();
244
245    // Build the filter initial estimate, which we will reuse in the filter.
246    let initial_estimate = sc.to_estimate()?;
247
248    println!("== FILTER STATE ==\n{sc_seed:x}\n{initial_estimate}");
249
250    // Build the SNC in the Moon J2000 frame, specified as a velocity noise over time.
251    let process_noise = ProcessNoise3D::from_velocity_km_s(
252        &[1.8e-9, 1.8e-9, 1.8e-9],
253        1 * Unit::Hour,
254        10 * Unit::Minute,
255        None,
256    );
257
258    println!("{process_noise}");
259
260    // We'll set up the OD process to reject measurements whose residuals are move than 3 sigmas away from what we expect.
261    let odp = SpacecraftKalmanOD::new(
262        setup,
263        KalmanVariant::ReferenceUpdate,
264        Some(ResidRejectCrit::default()),
265        devices,
266        almanac.clone(),
267    )
268    .with_process_noise(process_noise);
269
270    let od_sol = odp.process_arc(initial_estimate, &arc)?;
271
272    let ric_err = traj_as_flown
273        .at(od_sol.estimates.last().unwrap().epoch())?
274        .orbit
275        .ric_difference(&od_sol.estimates.last().unwrap().orbital_state())?;
276    println!("== RIC at end ==");
277    println!("RIC Position (m): {}", ric_err.radius_km * 1e3);
278    println!("RIC Velocity (m/s): {}", ric_err.velocity_km_s * 1e3);
279
280    println!(
281        "Num residuals rejected: #{}",
282        od_sol.rejected_residuals().len()
283    );
284    println!(
285        "Percentage within +/-3: {}",
286        od_sol.residual_ratio_within_threshold(3.0).unwrap()
287    );
288    println!("Ratios normal? {}", od_sol.is_normal(None).unwrap());
289
290    od_sol.to_parquet("./04_lro_od_results.parquet", ExportCfg::default())?;
291
292    // In our case, we have the truth trajectory from NASA.
293    // So we can compute the RIC state difference between the real LRO ephem and what we've just estimated.
294    // Export the OD trajectory first.
295    let od_trajectory = od_sol.to_traj()?;
296    // Build the RIC difference.
297    od_trajectory.ric_diff_to_parquet(
298        &traj_as_flown,
299        "./04_lro_od_truth_error.parquet",
300        ExportCfg::default(),
301    )?;
302
303    Ok(())
304}
examples/01_orbit_prop/main.rs (line 41)
30fn main() -> Result<(), Box<dyn Error>> {
31    pel::init();
32    // Dynamics models require planetary constants and ephemerides to be defined.
33    // Let's start by grabbing those by using ANISE's latest MetaAlmanac.
34    // This will automatically download the DE440s planetary ephemeris,
35    // the daily-updated Earth Orientation Parameters, the high fidelity Moon orientation
36    // parameters (for the Moon Mean Earth and Moon Principal Axes frames), and the PCK11
37    // planetary constants kernels.
38    // For details, refer to https://github.com/nyx-space/anise/blob/master/data/latest.dhall.
39    // Note that we place the Almanac into an Arc so we can clone it cheaply and provide read-only
40    // references to many functions.
41    let almanac = Arc::new(MetaAlmanac::latest().map_err(Box::new)?);
42    // Define the orbit epoch
43    let epoch = Epoch::from_gregorian_utc_hms(2024, 2, 29, 12, 13, 14);
44
45    // Define the orbit.
46    // First we need to fetch the Earth J2000 from information from the Almanac.
47    // This allows the frame to include the gravitational parameters and the shape of the Earth,
48    // defined as a tri-axial ellipoid. Note that this shape can be changed manually or in the Almanac
49    // by loading a different set of planetary constants.
50    let earth_j2000 = almanac.frame_from_uid(EARTH_J2000)?;
51
52    let orbit =
53        Orbit::try_keplerian_altitude(300.0, 0.015, 68.5, 65.2, 75.0, 0.0, epoch, earth_j2000)?;
54    // Print in in Keplerian form.
55    println!("{orbit:x}");
56
57    // There are two ways to propagate an orbit. We can make a quick approximation assuming only two-body
58    // motion. This is a useful first order approximation but it isn't used in real-world applications.
59
60    // This approach is a feature of ANISE.
61    let future_orbit_tb = orbit.at_epoch(epoch + Unit::Day * 3)?;
62    println!("{future_orbit_tb:x}");
63
64    // Two body propagation relies solely on Kepler's laws, so only the true anomaly will change.
65    println!(
66        "SMA changed by {:.3e} km",
67        orbit.sma_km()? - future_orbit_tb.sma_km()?
68    );
69    println!(
70        "ECC changed by {:.3e}",
71        orbit.ecc()? - future_orbit_tb.ecc()?
72    );
73    println!(
74        "INC changed by {:.3e} deg",
75        orbit.inc_deg()? - future_orbit_tb.inc_deg()?
76    );
77    println!(
78        "RAAN changed by {:.3e} deg",
79        orbit.raan_deg()? - future_orbit_tb.raan_deg()?
80    );
81    println!(
82        "AOP changed by {:.3e} deg",
83        orbit.aop_deg()? - future_orbit_tb.aop_deg()?
84    );
85    println!(
86        "TA changed by {:.3} deg",
87        orbit.ta_deg()? - future_orbit_tb.ta_deg()?
88    );
89
90    // Nyx is used for high fidelity propagation, not Keplerian propagation as above.
91    // Nyx only propagates Spacecraft at the moment, which allows it to account for acceleration
92    // models such as solar radiation pressure.
93
94    // Let's build a cubesat sized spacecraft, with an SRP area of 10 cm^2 and a mass of 9.6 kg.
95    let sc = Spacecraft::builder()
96        .orbit(orbit)
97        .mass(Mass::from_dry_mass(9.60))
98        .srp(SRPData {
99            area_m2: 10e-4,
100            coeff_reflectivity: 1.1,
101        })
102        .build();
103    println!("{sc:x}");
104
105    // Set up the spacecraft dynamics.
106
107    // Specify that the orbital dynamics must account for the graviational pull of the Moon and the Sun.
108    // The gravity of the Earth will also be accounted for since the spaceraft in an Earth orbit.
109    let mut orbital_dyn = OrbitalDynamics::point_masses(vec![MOON, SUN]);
110
111    // We want to include the spherical harmonics, so let's download the gravitational data from the Nyx Cloud.
112    // We're using the JGM3 model here, which is the default in GMAT.
113    let mut jgm3_meta = MetaFile {
114        uri: "http://public-data.nyxspace.com/nyx/models/JGM3.cof.gz".to_string(),
115        crc32: Some(0xF446F027), // Specifying the CRC32 avoids redownloading it if it's cached.
116    };
117    // And let's download it if we don't have it yet.
118    jgm3_meta.process(true)?;
119
120    // Build the spherical harmonics.
121    // The harmonics must be computed in the body fixed frame.
122    // We're using the long term prediction of the Earth centered Earth fixed frame, IAU Earth.
123    let harmonics_21x21 = Harmonics::from_stor(
124        almanac.frame_from_uid(IAU_EARTH_FRAME)?,
125        HarmonicsMem::from_cof(&jgm3_meta.uri, 21, 21, true).unwrap(),
126    );
127
128    // Include the spherical harmonics into the orbital dynamics.
129    orbital_dyn.accel_models.push(harmonics_21x21);
130
131    // We define the solar radiation pressure, using the default solar flux and accounting only
132    // for the eclipsing caused by the Earth.
133    let srp_dyn = SolarPressure::default(EARTH_J2000, almanac.clone())?;
134
135    // Finalize setting up the dynamics, specifying the force models (orbital_dyn) separately from the
136    // acceleration models (SRP in this case). Use `from_models` to specify multiple accel models.
137    let dynamics = SpacecraftDynamics::from_model(orbital_dyn, srp_dyn);
138
139    println!("{dynamics}");
140
141    // Finally, let's propagate this orbit to the same epoch as above.
142    // The first returned value is the spacecraft state at the final epoch.
143    // The second value is the full trajectory where the step size is variable step used by the propagator.
144    let (future_sc, trajectory) = Propagator::default(dynamics)
145        .with(sc, almanac.clone())
146        .until_epoch_with_traj(future_orbit_tb.epoch)?;
147
148    println!("=== High fidelity propagation ===");
149    println!(
150        "SMA changed by {:.3} km",
151        orbit.sma_km()? - future_sc.orbit.sma_km()?
152    );
153    println!(
154        "ECC changed by {:.6}",
155        orbit.ecc()? - future_sc.orbit.ecc()?
156    );
157    println!(
158        "INC changed by {:.3e} deg",
159        orbit.inc_deg()? - future_sc.orbit.inc_deg()?
160    );
161    println!(
162        "RAAN changed by {:.3} deg",
163        orbit.raan_deg()? - future_sc.orbit.raan_deg()?
164    );
165    println!(
166        "AOP changed by {:.3} deg",
167        orbit.aop_deg()? - future_sc.orbit.aop_deg()?
168    );
169    println!(
170        "TA changed by {:.3} deg",
171        orbit.ta_deg()? - future_sc.orbit.ta_deg()?
172    );
173
174    // We also have access to the full trajectory throughout the propagation.
175    println!("{trajectory}");
176
177    // With the trajectory, let's build a few data products.
178
179    // 1. Export the trajectory as a CCSDS OEM version 2.0 file and as a parquet file, which includes the Keplerian orbital elements.
180
181    trajectory.to_oem_file(
182        "./01_cubesat_hf_prop.oem",
183        ExportCfg::builder().step(Unit::Minute * 2).build(),
184    )?;
185
186    trajectory.to_parquet_with_cfg(
187        "./01_cubesat_hf_prop.parquet",
188        ExportCfg::builder().step(Unit::Minute * 2).build(),
189        almanac.clone(),
190    )?;
191
192    // 2. Compare the difference in the radial-intrack-crosstrack frame between the high fidelity
193    // and Keplerian propagation. The RIC frame is commonly used to compute the difference in position
194    // and velocity of different spacecraft.
195    // 3. Compute the azimuth, elevation, range, and range-rate data of that spacecraft as seen from Boulder, CO, USA.
196
197    let boulder_station = GroundStation::from_point(
198        "Boulder, CO, USA".to_string(),
199        40.014984,   // latitude in degrees
200        -105.270546, // longitude in degrees
201        1.6550,      // altitude in kilometers
202        almanac.frame_from_uid(IAU_EARTH_FRAME)?,
203    );
204
205    // We iterate over the trajectory, grabbing a state every two minutes.
206    let mut offset_s = vec![];
207    let mut epoch_str = vec![];
208    let mut ric_x_km = vec![];
209    let mut ric_y_km = vec![];
210    let mut ric_z_km = vec![];
211    let mut ric_vx_km_s = vec![];
212    let mut ric_vy_km_s = vec![];
213    let mut ric_vz_km_s = vec![];
214
215    let mut azimuth_deg = vec![];
216    let mut elevation_deg = vec![];
217    let mut range_km = vec![];
218    let mut range_rate_km_s = vec![];
219    for state in trajectory.every(Unit::Minute * 2) {
220        // Try to compute the Keplerian/two body state just in time.
221        // This method occasionally fails to converge on an appropriate true anomaly
222        // from the mean anomaly. If that happens, we just skip this state.
223        // The high fidelity and Keplerian states diverge continuously, and we're curious
224        // about the divergence in this quick analysis.
225        let this_epoch = state.epoch();
226        match orbit.at_epoch(this_epoch) {
227            Ok(tb_then) => {
228                offset_s.push((this_epoch - orbit.epoch).to_seconds());
229                epoch_str.push(format!("{this_epoch}"));
230                // Compute the two body state just in time.
231                let ric = state.orbit.ric_difference(&tb_then)?;
232                ric_x_km.push(ric.radius_km.x);
233                ric_y_km.push(ric.radius_km.y);
234                ric_z_km.push(ric.radius_km.z);
235                ric_vx_km_s.push(ric.velocity_km_s.x);
236                ric_vy_km_s.push(ric.velocity_km_s.y);
237                ric_vz_km_s.push(ric.velocity_km_s.z);
238
239                // Compute the AER data for each state.
240                let aer = almanac.azimuth_elevation_range_sez(
241                    state.orbit,
242                    boulder_station.to_orbit(this_epoch, &almanac)?,
243                    None,
244                    None,
245                )?;
246                azimuth_deg.push(aer.azimuth_deg);
247                elevation_deg.push(aer.elevation_deg);
248                range_km.push(aer.range_km);
249                range_rate_km_s.push(aer.range_rate_km_s);
250            }
251            Err(e) => warn!("{} {e}", state.epoch()),
252        };
253    }
254
255    // Build the data frames.
256    let ric_df = df!(
257        "Offset (s)" => offset_s.clone(),
258        "Epoch" => epoch_str.clone(),
259        "RIC X (km)" => ric_x_km,
260        "RIC Y (km)" => ric_y_km,
261        "RIC Z (km)" => ric_z_km,
262        "RIC VX (km/s)" => ric_vx_km_s,
263        "RIC VY (km/s)" => ric_vy_km_s,
264        "RIC VZ (km/s)" => ric_vz_km_s,
265    )?;
266
267    println!("RIC difference at start\n{}", ric_df.head(Some(10)));
268    println!("RIC difference at end\n{}", ric_df.tail(Some(10)));
269
270    let aer_df = df!(
271        "Offset (s)" => offset_s.clone(),
272        "Epoch" => epoch_str.clone(),
273        "azimuth (deg)" => azimuth_deg,
274        "elevation (deg)" => elevation_deg,
275        "range (km)" => range_km,
276        "range rate (km/s)" => range_rate_km_s,
277    )?;
278
279    // Finally, let's see when the spacecraft is visible, assuming 15 degrees minimum elevation.
280    let mask = aer_df
281        .column("elevation (deg)")?
282        .gt(&Column::Scalar(ScalarColumn::new(
283            "elevation mask (deg)".into(),
284            Scalar::new(DataType::Float64, AnyValue::Float64(15.0)),
285            offset_s.len(),
286        )))?;
287    let cubesat_visible = aer_df.filter(&mask)?;
288
289    println!("{cubesat_visible}");
290
291    Ok(())
292}
1.60.0 · Source

pub fn new_cyclic<F>(data_fn: F) -> Arc<T>
where F: FnOnce(&Weak<T>) -> T,

Constructs a new Arc<T> while giving you a Weak<T> to the allocation, to allow you to construct a T which holds a weak pointer to itself.

Generally, a structure circularly referencing itself, either directly or indirectly, should not hold a strong reference to itself to prevent a memory leak. Using this function, you get access to the weak pointer during the initialization of T, before the Arc<T> is created, such that you can clone and store it inside the T.

new_cyclic first allocates the managed allocation for the Arc<T>, then calls your closure, giving it a Weak<T> to this allocation, and only afterwards completes the construction of the Arc<T> by placing the T returned from your closure into the allocation.

Since the new Arc<T> is not fully-constructed until Arc<T>::new_cyclic returns, calling upgrade on the weak reference inside your closure will fail and result in a None value.

§Panics

If data_fn panics, the panic is propagated to the caller, and the temporary Weak<T> is dropped normally.

§Example
use std::sync::{Arc, Weak};

struct Gadget {
    me: Weak<Gadget>,
}

impl Gadget {
    /// Constructs a reference counted Gadget.
    fn new() -> Arc<Self> {
        // `me` is a `Weak<Gadget>` pointing at the new allocation of the
        // `Arc` we're constructing.
        Arc::new_cyclic(|me| {
            // Create the actual struct here.
            Gadget { me: me.clone() }
        })
    }

    /// Returns a reference counted pointer to Self.
    fn me(&self) -> Arc<Self> {
        self.me.upgrade().unwrap()
    }
}
1.82.0 · Source

pub fn new_uninit() -> Arc<MaybeUninit<T>>

Constructs a new Arc with uninitialized contents.

§Examples
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut five = Arc::<u32>::new_uninit();

// Deferred initialization:
Arc::get_mut(&mut five).unwrap().write(5);

let five = unsafe { five.assume_init() };

assert_eq!(*five, 5)
Source

pub fn new_zeroed() -> Arc<MaybeUninit<T>>

🔬This is a nightly-only experimental API. (new_zeroed_alloc)

Constructs a new Arc with uninitialized contents, with the memory being filled with 0 bytes.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature(new_zeroed_alloc)]

use std::sync::Arc;

let zero = Arc::<u32>::new_zeroed();
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0)
1.33.0 · Source

pub fn pin(data: T) -> Pin<Arc<T>>

Constructs a new Pin<Arc<T>>. If T does not implement Unpin, then data will be pinned in memory and unable to be moved.

Source

pub fn try_pin(data: T) -> Result<Pin<Arc<T>>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Pin<Arc<T>>, return an error if allocation fails.

Source

pub fn try_new(data: T) -> Result<Arc<T>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc<T>, returning an error if allocation fails.

§Examples
#![feature(allocator_api)]
use std::sync::Arc;

let five = Arc::try_new(5)?;
Source

pub fn try_new_uninit() -> Result<Arc<MaybeUninit<T>>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents, returning an error if allocation fails.

§Examples
#![feature(allocator_api)]
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut five = Arc::<u32>::try_new_uninit()?;

// Deferred initialization:
Arc::get_mut(&mut five).unwrap().write(5);

let five = unsafe { five.assume_init() };

assert_eq!(*five, 5);
Source

pub fn try_new_zeroed() -> Result<Arc<MaybeUninit<T>>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents, with the memory being filled with 0 bytes, returning an error if allocation fails.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature( allocator_api)]

use std::sync::Arc;

let zero = Arc::<u32>::try_new_zeroed()?;
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0);
Source§

impl<T, A> Arc<T, A>
where A: Allocator,

Source

pub fn new_in(data: T, alloc: A) -> Arc<T, A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc<T> in the provided allocator.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let five = Arc::new_in(5, System);
Source

pub fn new_uninit_in(alloc: A) -> Arc<MaybeUninit<T>, A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents in the provided allocator.

§Examples
#![feature(get_mut_unchecked)]
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let mut five = Arc::<u32, _>::new_uninit_in(System);

let five = unsafe {
    // Deferred initialization:
    Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);

    five.assume_init()
};

assert_eq!(*five, 5)
Source

pub fn new_zeroed_in(alloc: A) -> Arc<MaybeUninit<T>, A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents, with the memory being filled with 0 bytes, in the provided allocator.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let zero = Arc::<u32, _>::new_zeroed_in(System);
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0)
Source

pub fn new_cyclic_in<F>(data_fn: F, alloc: A) -> Arc<T, A>
where F: FnOnce(&Weak<T, A>) -> T,

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc<T, A> in the given allocator while giving you a Weak<T, A> to the allocation, to allow you to construct a T which holds a weak pointer to itself.

Generally, a structure circularly referencing itself, either directly or indirectly, should not hold a strong reference to itself to prevent a memory leak. Using this function, you get access to the weak pointer during the initialization of T, before the Arc<T, A> is created, such that you can clone and store it inside the T.

new_cyclic_in first allocates the managed allocation for the Arc<T, A>, then calls your closure, giving it a Weak<T, A> to this allocation, and only afterwards completes the construction of the Arc<T, A> by placing the T returned from your closure into the allocation.

Since the new Arc<T, A> is not fully-constructed until Arc<T, A>::new_cyclic_in returns, calling upgrade on the weak reference inside your closure will fail and result in a None value.

§Panics

If data_fn panics, the panic is propagated to the caller, and the temporary Weak<T> is dropped normally.

§Example

See new_cyclic

Source

pub fn pin_in(data: T, alloc: A) -> Pin<Arc<T, A>>
where A: 'static,

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Pin<Arc<T, A>> in the provided allocator. If T does not implement Unpin, then data will be pinned in memory and unable to be moved.

Source

pub fn try_pin_in(data: T, alloc: A) -> Result<Pin<Arc<T, A>>, AllocError>
where A: 'static,

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Pin<Arc<T, A>> in the provided allocator, return an error if allocation fails.

Source

pub fn try_new_in(data: T, alloc: A) -> Result<Arc<T, A>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc<T, A> in the provided allocator, returning an error if allocation fails.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let five = Arc::try_new_in(5, System)?;
Source

pub fn try_new_uninit_in(alloc: A) -> Result<Arc<MaybeUninit<T>, A>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents, in the provided allocator, returning an error if allocation fails.

§Examples
#![feature(allocator_api)]
#![feature(get_mut_unchecked)]

use std::sync::Arc;
use std::alloc::System;

let mut five = Arc::<u32, _>::try_new_uninit_in(System)?;

let five = unsafe {
    // Deferred initialization:
    Arc::get_mut_unchecked(&mut five).as_mut_ptr().write(5);

    five.assume_init()
};

assert_eq!(*five, 5);
Source

pub fn try_new_zeroed_in(alloc: A) -> Result<Arc<MaybeUninit<T>, A>, AllocError>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new Arc with uninitialized contents, with the memory being filled with 0 bytes, in the provided allocator, returning an error if allocation fails.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let zero = Arc::<u32, _>::try_new_zeroed_in(System)?;
let zero = unsafe { zero.assume_init() };

assert_eq!(*zero, 0);
1.4.0 · Source

pub fn try_unwrap(this: Arc<T, A>) -> Result<T, Arc<T, A>>

Returns the inner value, if the Arc has exactly one strong reference.

Otherwise, an Err is returned with the same Arc that was passed in.

This will succeed even if there are outstanding weak references.

It is strongly recommended to use Arc::into_inner instead if you don’t keep the Arc in the Err case. Immediately dropping the Err-value, as the expression Arc::try_unwrap(this).ok() does, can cause the strong count to drop to zero and the inner value of the Arc to be dropped. For instance, if two threads execute such an expression in parallel, there is a race condition without the possibility of unsafety: The threads could first both check whether they own the last instance in Arc::try_unwrap, determine that they both do not, and then both discard and drop their instance in the call to ok. In this scenario, the value inside the Arc is safely destroyed by exactly one of the threads, but neither thread will ever be able to use the value.

§Examples
use std::sync::Arc;

let x = Arc::new(3);
assert_eq!(Arc::try_unwrap(x), Ok(3));

let x = Arc::new(4);
let _y = Arc::clone(&x);
assert_eq!(*Arc::try_unwrap(x).unwrap_err(), 4);
1.70.0 · Source

pub fn into_inner(this: Arc<T, A>) -> Option<T>

Returns the inner value, if the Arc has exactly one strong reference.

Otherwise, None is returned and the Arc is dropped.

This will succeed even if there are outstanding weak references.

If Arc::into_inner is called on every clone of this Arc, it is guaranteed that exactly one of the calls returns the inner value. This means in particular that the inner value is not dropped.

Arc::try_unwrap is conceptually similar to Arc::into_inner, but it is meant for different use-cases. If used as a direct replacement for Arc::into_inner anyway, such as with the expression Arc::try_unwrap(this).ok(), then it does not give the same guarantee as described in the previous paragraph. For more information, see the examples below and read the documentation of Arc::try_unwrap.

§Examples

Minimal example demonstrating the guarantee that Arc::into_inner gives.

use std::sync::Arc;

let x = Arc::new(3);
let y = Arc::clone(&x);

// Two threads calling `Arc::into_inner` on both clones of an `Arc`:
let x_thread = std::thread::spawn(|| Arc::into_inner(x));
let y_thread = std::thread::spawn(|| Arc::into_inner(y));

let x_inner_value = x_thread.join().unwrap();
let y_inner_value = y_thread.join().unwrap();

// One of the threads is guaranteed to receive the inner value:
assert!(matches!(
    (x_inner_value, y_inner_value),
    (None, Some(3)) | (Some(3), None)
));
// The result could also be `(None, None)` if the threads called
// `Arc::try_unwrap(x).ok()` and `Arc::try_unwrap(y).ok()` instead.

A more practical example demonstrating the need for Arc::into_inner:

use std::sync::Arc;

// Definition of a simple singly linked list using `Arc`:
#[derive(Clone)]
struct LinkedList<T>(Option<Arc<Node<T>>>);
struct Node<T>(T, Option<Arc<Node<T>>>);

// Dropping a long `LinkedList<T>` relying on the destructor of `Arc`
// can cause a stack overflow. To prevent this, we can provide a
// manual `Drop` implementation that does the destruction in a loop:
impl<T> Drop for LinkedList<T> {
    fn drop(&mut self) {
        let mut link = self.0.take();
        while let Some(arc_node) = link.take() {
            if let Some(Node(_value, next)) = Arc::into_inner(arc_node) {
                link = next;
            }
        }
    }
}

// Implementation of `new` and `push` omitted
impl<T> LinkedList<T> {
    /* ... */
}

// The following code could have still caused a stack overflow
// despite the manual `Drop` impl if that `Drop` impl had used
// `Arc::try_unwrap(arc).ok()` instead of `Arc::into_inner(arc)`.

// Create a long list and clone it
let mut x = LinkedList::new();
let size = 100000;
for i in 0..size {
    x.push(i); // Adds i to the front of x
}
let y = x.clone();

// Drop the clones in parallel
let x_thread = std::thread::spawn(|| drop(x));
let y_thread = std::thread::spawn(|| drop(y));
x_thread.join().unwrap();
y_thread.join().unwrap();
Source§

impl<T> Arc<[T]>

1.82.0 · Source

pub fn new_uninit_slice(len: usize) -> Arc<[MaybeUninit<T>]>

Constructs a new atomically reference-counted slice with uninitialized contents.

§Examples
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut values = Arc::<[u32]>::new_uninit_slice(3);

// Deferred initialization:
let data = Arc::get_mut(&mut values).unwrap();
data[0].write(1);
data[1].write(2);
data[2].write(3);

let values = unsafe { values.assume_init() };

assert_eq!(*values, [1, 2, 3])
Source

pub fn new_zeroed_slice(len: usize) -> Arc<[MaybeUninit<T>]>

🔬This is a nightly-only experimental API. (new_zeroed_alloc)

Constructs a new atomically reference-counted slice with uninitialized contents, with the memory being filled with 0 bytes.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature(new_zeroed_alloc)]

use std::sync::Arc;

let values = Arc::<[u32]>::new_zeroed_slice(3);
let values = unsafe { values.assume_init() };

assert_eq!(*values, [0, 0, 0])
Source

pub fn into_array<const N: usize>(self) -> Option<Arc<[T; N]>>

🔬This is a nightly-only experimental API. (slice_as_array)

Converts the reference-counted slice into a reference-counted array.

This operation does not reallocate; the underlying array of the slice is simply reinterpreted as an array type.

If N is not exactly equal to the length of self, then this method returns None.

Source§

impl<T, A> Arc<[T], A>
where A: Allocator,

Source

pub fn new_uninit_slice_in(len: usize, alloc: A) -> Arc<[MaybeUninit<T>], A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new atomically reference-counted slice with uninitialized contents in the provided allocator.

§Examples
#![feature(get_mut_unchecked)]
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let mut values = Arc::<[u32], _>::new_uninit_slice_in(3, System);

let values = unsafe {
    // Deferred initialization:
    Arc::get_mut_unchecked(&mut values)[0].as_mut_ptr().write(1);
    Arc::get_mut_unchecked(&mut values)[1].as_mut_ptr().write(2);
    Arc::get_mut_unchecked(&mut values)[2].as_mut_ptr().write(3);

    values.assume_init()
};

assert_eq!(*values, [1, 2, 3])
Source

pub fn new_zeroed_slice_in(len: usize, alloc: A) -> Arc<[MaybeUninit<T>], A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs a new atomically reference-counted slice with uninitialized contents, with the memory being filled with 0 bytes, in the provided allocator.

See MaybeUninit::zeroed for examples of correct and incorrect usage of this method.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let values = Arc::<[u32], _>::new_zeroed_slice_in(3, System);
let values = unsafe { values.assume_init() };

assert_eq!(*values, [0, 0, 0])
Source§

impl<T, A> Arc<MaybeUninit<T>, A>
where A: Allocator,

1.82.0 · Source

pub unsafe fn assume_init(self) -> Arc<T, A>

Converts to Arc<T>.

§Safety

As with MaybeUninit::assume_init, it is up to the caller to guarantee that the inner value really is in an initialized state. Calling this when the content is not yet fully initialized causes immediate undefined behavior.

§Examples
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut five = Arc::<u32>::new_uninit();

// Deferred initialization:
Arc::get_mut(&mut five).unwrap().write(5);

let five = unsafe { five.assume_init() };

assert_eq!(*five, 5)
Source§

impl<T, A> Arc<[MaybeUninit<T>], A>
where A: Allocator,

1.82.0 · Source

pub unsafe fn assume_init(self) -> Arc<[T], A>

Converts to Arc<[T]>.

§Safety

As with MaybeUninit::assume_init, it is up to the caller to guarantee that the inner value really is in an initialized state. Calling this when the content is not yet fully initialized causes immediate undefined behavior.

§Examples
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut values = Arc::<[u32]>::new_uninit_slice(3);

// Deferred initialization:
let data = Arc::get_mut(&mut values).unwrap();
data[0].write(1);
data[1].write(2);
data[2].write(3);

let values = unsafe { values.assume_init() };

assert_eq!(*values, [1, 2, 3])
Source§

impl<T> Arc<T>
where T: ?Sized,

1.17.0 · Source

pub unsafe fn from_raw(ptr: *const T) -> Arc<T>

Constructs an Arc<T> from a raw pointer.

The raw pointer must have been previously returned by a call to Arc<U>::into_raw with the following requirements:

  • If U is sized, it must have the same size and alignment as T. This is trivially true if U is T.
  • If U is unsized, its data pointer must have the same size and alignment as T. This is trivially true if Arc<U> was constructed through Arc<T> and then converted to Arc<U> through an unsized coercion.

Note that if U or U’s data pointer is not T but has the same size and alignment, this is basically like transmuting references of different types. See mem::transmute for more information on what restrictions apply in this case.

The raw pointer must point to a block of memory allocated by the global allocator.

The user of from_raw has to make sure a specific value of T is only dropped once.

This function is unsafe because improper use may lead to memory unsafety, even if the returned Arc<T> is never accessed.

§Examples
use std::sync::Arc;

let x = Arc::new("hello".to_owned());
let x_ptr = Arc::into_raw(x);

unsafe {
    // Convert back to an `Arc` to prevent leak.
    let x = Arc::from_raw(x_ptr);
    assert_eq!(&*x, "hello");

    // Further calls to `Arc::from_raw(x_ptr)` would be memory-unsafe.
}

// The memory was freed when `x` went out of scope above, so `x_ptr` is now dangling!

Convert a slice back into its original array:

use std::sync::Arc;

let x: Arc<[u32]> = Arc::new([1, 2, 3]);
let x_ptr: *const [u32] = Arc::into_raw(x);

unsafe {
    let x: Arc<[u32; 3]> = Arc::from_raw(x_ptr.cast::<[u32; 3]>());
    assert_eq!(&*x, &[1, 2, 3]);
}
1.17.0 · Source

pub fn into_raw(this: Arc<T>) -> *const T

Consumes the Arc, returning the wrapped pointer.

To avoid a memory leak the pointer must be converted back to an Arc using Arc::from_raw.

§Examples
use std::sync::Arc;

let x = Arc::new("hello".to_owned());
let x_ptr = Arc::into_raw(x);
assert_eq!(unsafe { &*x_ptr }, "hello");
1.51.0 · Source

pub unsafe fn increment_strong_count(ptr: *const T)

Increments the strong reference count on the Arc<T> associated with the provided pointer by one.

§Safety

The pointer must have been obtained through Arc::into_raw and must satisfy the same layout requirements specified in Arc::from_raw_in. The associated Arc instance must be valid (i.e. the strong count must be at least 1) for the duration of this method, and ptr must point to a block of memory allocated by the global allocator.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

unsafe {
    let ptr = Arc::into_raw(five);
    Arc::increment_strong_count(ptr);

    // This assertion is deterministic because we haven't shared
    // the `Arc` between threads.
    let five = Arc::from_raw(ptr);
    assert_eq!(2, Arc::strong_count(&five));
}
1.51.0 · Source

pub unsafe fn decrement_strong_count(ptr: *const T)

Decrements the strong reference count on the Arc<T> associated with the provided pointer by one.

§Safety

The pointer must have been obtained through Arc::into_raw and must satisfy the same layout requirements specified in Arc::from_raw_in. The associated Arc instance must be valid (i.e. the strong count must be at least 1) when invoking this method, and ptr must point to a block of memory allocated by the global allocator. This method can be used to release the final Arc and backing storage, but should not be called after the final Arc has been released.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

unsafe {
    let ptr = Arc::into_raw(five);
    Arc::increment_strong_count(ptr);

    // Those assertions are deterministic because we haven't shared
    // the `Arc` between threads.
    let five = Arc::from_raw(ptr);
    assert_eq!(2, Arc::strong_count(&five));
    Arc::decrement_strong_count(ptr);
    assert_eq!(1, Arc::strong_count(&five));
}
Source§

impl<T, A> Arc<T, A>
where A: Allocator, T: ?Sized,

Source

pub fn allocator(this: &Arc<T, A>) -> &A

🔬This is a nightly-only experimental API. (allocator_api)

Returns a reference to the underlying allocator.

Note: this is an associated function, which means that you have to call it as Arc::allocator(&a) instead of a.allocator(). This is so that there is no conflict with a method on the inner type.

Source

pub fn into_raw_with_allocator(this: Arc<T, A>) -> (*const T, A)

🔬This is a nightly-only experimental API. (allocator_api)

Consumes the Arc, returning the wrapped pointer and allocator.

To avoid a memory leak the pointer must be converted back to an Arc using Arc::from_raw_in.

§Examples
#![feature(allocator_api)]
use std::sync::Arc;
use std::alloc::System;

let x = Arc::new_in("hello".to_owned(), System);
let (ptr, alloc) = Arc::into_raw_with_allocator(x);
assert_eq!(unsafe { &*ptr }, "hello");
let x = unsafe { Arc::from_raw_in(ptr, alloc) };
assert_eq!(&*x, "hello");
1.45.0 · Source

pub fn as_ptr(this: &Arc<T, A>) -> *const T

Provides a raw pointer to the data.

The counts are not affected in any way and the Arc is not consumed. The pointer is valid for as long as there are strong counts in the Arc.

§Examples
use std::sync::Arc;

let x = Arc::new("hello".to_owned());
let y = Arc::clone(&x);
let x_ptr = Arc::as_ptr(&x);
assert_eq!(x_ptr, Arc::as_ptr(&y));
assert_eq!(unsafe { &*x_ptr }, "hello");
Source

pub unsafe fn from_raw_in(ptr: *const T, alloc: A) -> Arc<T, A>

🔬This is a nightly-only experimental API. (allocator_api)

Constructs an Arc<T, A> from a raw pointer.

The raw pointer must have been previously returned by a call to Arc<U, A>::into_raw with the following requirements:

  • If U is sized, it must have the same size and alignment as T. This is trivially true if U is T.
  • If U is unsized, its data pointer must have the same size and alignment as T. This is trivially true if Arc<U> was constructed through Arc<T> and then converted to Arc<U> through an unsized coercion.

Note that if U or U’s data pointer is not T but has the same size and alignment, this is basically like transmuting references of different types. See mem::transmute for more information on what restrictions apply in this case.

The raw pointer must point to a block of memory allocated by alloc

The user of from_raw has to make sure a specific value of T is only dropped once.

This function is unsafe because improper use may lead to memory unsafety, even if the returned Arc<T> is never accessed.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let x = Arc::new_in("hello".to_owned(), System);
let (x_ptr, alloc) = Arc::into_raw_with_allocator(x);

unsafe {
    // Convert back to an `Arc` to prevent leak.
    let x = Arc::from_raw_in(x_ptr, System);
    assert_eq!(&*x, "hello");

    // Further calls to `Arc::from_raw(x_ptr)` would be memory-unsafe.
}

// The memory was freed when `x` went out of scope above, so `x_ptr` is now dangling!

Convert a slice back into its original array:

#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let x: Arc<[u32], _> = Arc::new_in([1, 2, 3], System);
let x_ptr: *const [u32] = Arc::into_raw_with_allocator(x).0;

unsafe {
    let x: Arc<[u32; 3], _> = Arc::from_raw_in(x_ptr.cast::<[u32; 3]>(), System);
    assert_eq!(&*x, &[1, 2, 3]);
}
1.4.0 · Source

pub fn downgrade(this: &Arc<T, A>) -> Weak<T, A>
where A: Clone,

Creates a new Weak pointer to this allocation.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

let weak_five = Arc::downgrade(&five);
1.15.0 · Source

pub fn weak_count(this: &Arc<T, A>) -> usize

Gets the number of Weak pointers to this allocation.

§Safety

This method by itself is safe, but using it correctly requires extra care. Another thread can change the weak count at any time, including potentially between calling this method and acting on the result.

§Examples
use std::sync::Arc;

let five = Arc::new(5);
let _weak_five = Arc::downgrade(&five);

// This assertion is deterministic because we haven't shared
// the `Arc` or `Weak` between threads.
assert_eq!(1, Arc::weak_count(&five));
1.15.0 · Source

pub fn strong_count(this: &Arc<T, A>) -> usize

Gets the number of strong (Arc) pointers to this allocation.

§Safety

This method by itself is safe, but using it correctly requires extra care. Another thread can change the strong count at any time, including potentially between calling this method and acting on the result.

§Examples
use std::sync::Arc;

let five = Arc::new(5);
let _also_five = Arc::clone(&five);

// This assertion is deterministic because we haven't shared
// the `Arc` between threads.
assert_eq!(2, Arc::strong_count(&five));
Source

pub unsafe fn increment_strong_count_in(ptr: *const T, alloc: A)
where A: Clone,

🔬This is a nightly-only experimental API. (allocator_api)

Increments the strong reference count on the Arc<T> associated with the provided pointer by one.

§Safety

The pointer must have been obtained through Arc::into_raw and must satisfy the same layout requirements specified in Arc::from_raw_in. The associated Arc instance must be valid (i.e. the strong count must be at least 1) for the duration of this method, and ptr must point to a block of memory allocated by alloc.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let five = Arc::new_in(5, System);

unsafe {
    let (ptr, _alloc) = Arc::into_raw_with_allocator(five);
    Arc::increment_strong_count_in(ptr, System);

    // This assertion is deterministic because we haven't shared
    // the `Arc` between threads.
    let five = Arc::from_raw_in(ptr, System);
    assert_eq!(2, Arc::strong_count(&five));
}
Source

pub unsafe fn decrement_strong_count_in(ptr: *const T, alloc: A)

🔬This is a nightly-only experimental API. (allocator_api)

Decrements the strong reference count on the Arc<T> associated with the provided pointer by one.

§Safety

The pointer must have been obtained through Arc::into_raw and must satisfy the same layout requirements specified in Arc::from_raw_in. The associated Arc instance must be valid (i.e. the strong count must be at least 1) when invoking this method, and ptr must point to a block of memory allocated by alloc. This method can be used to release the final Arc and backing storage, but should not be called after the final Arc has been released.

§Examples
#![feature(allocator_api)]

use std::sync::Arc;
use std::alloc::System;

let five = Arc::new_in(5, System);

unsafe {
    let (ptr, _alloc) = Arc::into_raw_with_allocator(five);
    Arc::increment_strong_count_in(ptr, System);

    // Those assertions are deterministic because we haven't shared
    // the `Arc` between threads.
    let five = Arc::from_raw_in(ptr, System);
    assert_eq!(2, Arc::strong_count(&five));
    Arc::decrement_strong_count_in(ptr, System);
    assert_eq!(1, Arc::strong_count(&five));
}
1.17.0 · Source

pub fn ptr_eq(this: &Arc<T, A>, other: &Arc<T, A>) -> bool

Returns true if the two Arcs point to the same allocation in a vein similar to ptr::eq. This function ignores the metadata of dyn Trait pointers.

§Examples
use std::sync::Arc;

let five = Arc::new(5);
let same_five = Arc::clone(&five);
let other_five = Arc::new(5);

assert!(Arc::ptr_eq(&five, &same_five));
assert!(!Arc::ptr_eq(&five, &other_five));
Source§

impl<T, A> Arc<T, A>
where T: CloneToUninit + ?Sized, A: Allocator + Clone,

1.4.0 · Source

pub fn make_mut(this: &mut Arc<T, A>) -> &mut T

Makes a mutable reference into the given Arc.

If there are other Arc pointers to the same allocation, then make_mut will clone the inner value to a new allocation to ensure unique ownership. This is also referred to as clone-on-write.

However, if there are no other Arc pointers to this allocation, but some Weak pointers, then the Weak pointers will be dissociated and the inner value will not be cloned.

See also get_mut, which will fail rather than cloning the inner value or dissociating Weak pointers.

§Examples
use std::sync::Arc;

let mut data = Arc::new(5);

*Arc::make_mut(&mut data) += 1;         // Won't clone anything
let mut other_data = Arc::clone(&data); // Won't clone inner data
*Arc::make_mut(&mut data) += 1;         // Clones inner data
*Arc::make_mut(&mut data) += 1;         // Won't clone anything
*Arc::make_mut(&mut other_data) *= 2;   // Won't clone anything

// Now `data` and `other_data` point to different allocations.
assert_eq!(*data, 8);
assert_eq!(*other_data, 12);

Weak pointers will be dissociated:

use std::sync::Arc;

let mut data = Arc::new(75);
let weak = Arc::downgrade(&data);

assert!(75 == *data);
assert!(75 == *weak.upgrade().unwrap());

*Arc::make_mut(&mut data) += 1;

assert!(76 == *data);
assert!(weak.upgrade().is_none());
Source§

impl<T, A> Arc<T, A>
where T: Clone, A: Allocator,

1.76.0 · Source

pub fn unwrap_or_clone(this: Arc<T, A>) -> T

If we have the only reference to T then unwrap it. Otherwise, clone T and return the clone.

Assuming arc_t is of type Arc<T>, this function is functionally equivalent to (*arc_t).clone(), but will avoid cloning the inner value where possible.

§Examples
let inner = String::from("test");
let ptr = inner.as_ptr();

let arc = Arc::new(inner);
let inner = Arc::unwrap_or_clone(arc);
// The inner value was not cloned
assert!(ptr::eq(ptr, inner.as_ptr()));

let arc = Arc::new(inner);
let arc2 = arc.clone();
let inner = Arc::unwrap_or_clone(arc);
// Because there were 2 references, we had to clone the inner value.
assert!(!ptr::eq(ptr, inner.as_ptr()));
// `arc2` is the last reference, so when we unwrap it we get back
// the original `String`.
let inner = Arc::unwrap_or_clone(arc2);
assert!(ptr::eq(ptr, inner.as_ptr()));
Source§

impl<T, A> Arc<T, A>
where A: Allocator, T: ?Sized,

1.4.0 · Source

pub fn get_mut(this: &mut Arc<T, A>) -> Option<&mut T>

Returns a mutable reference into the given Arc, if there are no other Arc or Weak pointers to the same allocation.

Returns None otherwise, because it is not safe to mutate a shared value.

See also make_mut, which will clone the inner value when there are other Arc pointers.

§Examples
use std::sync::Arc;

let mut x = Arc::new(3);
*Arc::get_mut(&mut x).unwrap() = 4;
assert_eq!(*x, 4);

let _y = Arc::clone(&x);
assert!(Arc::get_mut(&mut x).is_none());
Source

pub unsafe fn get_mut_unchecked(this: &mut Arc<T, A>) -> &mut T

🔬This is a nightly-only experimental API. (get_mut_unchecked)

Returns a mutable reference into the given Arc, without any check.

See also get_mut, which is safe and does appropriate checks.

§Safety

If any other Arc or Weak pointers to the same allocation exist, then they must not be dereferenced or have active borrows for the duration of the returned borrow, and their inner type must be exactly the same as the inner type of this Rc (including lifetimes). This is trivially the case if no such pointers exist, for example immediately after Arc::new.

§Examples
#![feature(get_mut_unchecked)]

use std::sync::Arc;

let mut x = Arc::new(String::new());
unsafe {
    Arc::get_mut_unchecked(&mut x).push_str("foo")
}
assert_eq!(*x, "foo");

Other Arc pointers to the same allocation must be to the same type.

#![feature(get_mut_unchecked)]

use std::sync::Arc;

let x: Arc<str> = Arc::from("Hello, world!");
let mut y: Arc<[u8]> = x.clone().into();
unsafe {
    // this is Undefined Behavior, because x's inner type is str, not [u8]
    Arc::get_mut_unchecked(&mut y).fill(0xff); // 0xff is invalid in UTF-8
}
println!("{}", &*x); // Invalid UTF-8 in a str

Other Arc pointers to the same allocation must be to the exact same type, including lifetimes.

#![feature(get_mut_unchecked)]

use std::sync::Arc;

let x: Arc<&str> = Arc::new("Hello, world!");
{
    let s = String::from("Oh, no!");
    let mut y: Arc<&str> = x.clone();
    unsafe {
        // this is Undefined Behavior, because x's inner type
        // is &'long str, not &'short str
        *Arc::get_mut_unchecked(&mut y) = &s;
    }
}
println!("{}", &*x); // Use-after-free
Source

pub fn is_unique(this: &Arc<T, A>) -> bool

🔬This is a nightly-only experimental API. (arc_is_unique)

Determine whether this is the unique reference to the underlying data.

Returns true if there are no other Arc or Weak pointers to the same allocation; returns false otherwise.

If this function returns true, then is guaranteed to be safe to call get_mut_unchecked on this Arc, so long as no clones occur in between.

§Examples
#![feature(arc_is_unique)]

use std::sync::Arc;

let x = Arc::new(3);
assert!(Arc::is_unique(&x));

let y = Arc::clone(&x);
assert!(!Arc::is_unique(&x));
drop(y);

// Weak references also count, because they could be upgraded at any time.
let z = Arc::downgrade(&x);
assert!(!Arc::is_unique(&x));
§Pointer invalidation

This function will always return the same value as Arc::get_mut(arc).is_some(). However, unlike that operation it does not produce any mutable references to the underlying data, meaning no pointers to the data inside the Arc are invalidated by the call. Thus, the following code is valid, even though it would be UB if it used Arc::get_mut:

#![feature(arc_is_unique)]

use std::sync::Arc;

let arc = Arc::new(5);
let pointer: *const i32 = &*arc;
assert!(Arc::is_unique(&arc));
assert_eq!(unsafe { *pointer }, 5);
§Atomic orderings

Concurrent drops to other Arc pointers to the same allocation will synchronize with this call - that is, this call performs an Acquire operation on the underlying strong and weak ref counts. This ensures that calling get_mut_unchecked is safe.

Note that this operation requires locking the weak ref count, so concurrent calls to downgrade may spin-loop for a short period of time.

Source§

impl<A> Arc<dyn Any + Sync + Send, A>
where A: Allocator,

1.29.0 · Source

pub fn downcast<T>(self) -> Result<Arc<T, A>, Arc<dyn Any + Sync + Send, A>>
where T: Any + Send + Sync,

Attempts to downcast the Arc<dyn Any + Send + Sync> to a concrete type.

§Examples
use std::any::Any;
use std::sync::Arc;

fn print_if_string(value: Arc<dyn Any + Send + Sync>) {
    if let Ok(string) = value.downcast::<String>() {
        println!("String ({}): {}", string.len(), string);
    }
}

let my_string = "Hello World".to_string();
print_if_string(Arc::new(my_string));
print_if_string(Arc::new(0i8));
Source

pub unsafe fn downcast_unchecked<T>(self) -> Arc<T, A>
where T: Any + Send + Sync,

🔬This is a nightly-only experimental API. (downcast_unchecked)

Downcasts the Arc<dyn Any + Send + Sync> to a concrete type.

For a safe alternative see downcast.

§Examples
#![feature(downcast_unchecked)]

use std::any::Any;
use std::sync::Arc;

let x: Arc<dyn Any + Send + Sync> = Arc::new(1_usize);

unsafe {
    assert_eq!(*x.downcast_unchecked::<usize>(), 1);
}
§Safety

The contained value must be of type T. Calling this method with the incorrect type is undefined behavior.

Trait Implementations§

§

impl Array for Arc<dyn Array>

Ergonomics: Allow use of an ArrayRef as an &dyn Array

§

fn shrink_to_fit(&mut self)

For shared buffers, this is a no-op.

§

fn as_any(&self) -> &(dyn Any + 'static)

Returns the array as Any so that it can be downcasted to a specific implementation. Read more
§

fn to_data(&self) -> ArrayData

Returns the underlying data of this array
§

fn into_data(self) -> ArrayData

Returns the underlying data of this array Read more
§

fn data_type(&self) -> &DataType

Returns a reference to the [DataType] of this array. Read more
§

fn slice(&self, offset: usize, length: usize) -> Arc<dyn Array>

Returns a zero-copy slice of this array with the indicated offset and length. Read more
§

fn len(&self) -> usize

Returns the length (i.e., number of elements) of this array. Read more
§

fn is_empty(&self) -> bool

Returns whether this array is empty. Read more
§

fn offset(&self) -> usize

Returns the offset into the underlying data used by this array(-slice). Note that the underlying data can be shared by many arrays. This defaults to 0. Read more
§

fn nulls(&self) -> Option<&NullBuffer>

Returns the null buffer of this array if any. Read more
§

fn logical_nulls(&self) -> Option<NullBuffer>

Returns a potentially computed [NullBuffer] that represents the logical null values of this array, if any. Read more
§

fn is_null(&self, index: usize) -> bool

Returns whether the element at index is null according to [Array::nulls] Read more
§

fn is_valid(&self, index: usize) -> bool

Returns whether the element at index is not null, the opposite of [Self::is_null]. Read more
§

fn null_count(&self) -> usize

Returns the total number of physical null values in this array. Read more
§

fn logical_null_count(&self) -> usize

Returns the total number of logical null values in this array. Read more
§

fn is_nullable(&self) -> bool

Returns false if the array is guaranteed to not contain any logical nulls Read more
§

fn get_buffer_memory_size(&self) -> usize

Returns the total number of bytes of memory pointed to by this array. The buffers store bytes in the Arrow memory format, and include the data as well as the validity map. Note that this does not always correspond to the exact memory usage of an array, since multiple arrays can share the same buffers or slices thereof.
§

fn get_array_memory_size(&self) -> usize

Returns the total number of bytes of memory occupied physically by this array. This value will always be greater than returned by get_buffer_memory_size() and includes the overhead of the data structures that contain the pointers to the various buffers.
§

impl AsArray for Arc<dyn Array>

§

fn as_boolean_opt(&self) -> Option<&BooleanArray>

Downcast this to a [BooleanArray] returning None if not possible
§

fn as_primitive_opt<T>(&self) -> Option<&PrimitiveArray<T>>
where T: ArrowPrimitiveType,

Downcast this to a [PrimitiveArray] returning None if not possible
§

fn as_bytes_opt<T>(&self) -> Option<&GenericByteArray<T>>
where T: ByteArrayType,

Downcast this to a [GenericByteArray] returning None if not possible
§

fn as_byte_view_opt<T>(&self) -> Option<&GenericByteViewArray<T>>
where T: ByteViewType,

Downcast this to a [GenericByteViewArray] returning None if not possible
§

fn as_struct_opt(&self) -> Option<&StructArray>

Downcast this to a [StructArray] returning None if not possible
§

fn as_union_opt(&self) -> Option<&UnionArray>

Downcast this to a [UnionArray] returning None if not possible
§

fn as_list_opt<O>(&self) -> Option<&GenericListArray<O>>
where O: OffsetSizeTrait,

Downcast this to a [GenericListArray] returning None if not possible
§

fn as_list_view_opt<O>(&self) -> Option<&GenericListViewArray<O>>
where O: OffsetSizeTrait,

Downcast this to a [GenericListViewArray] returning None if not possible
§

fn as_fixed_size_binary_opt(&self) -> Option<&FixedSizeBinaryArray>

Downcast this to a [FixedSizeBinaryArray] returning None if not possible
§

fn as_fixed_size_list_opt(&self) -> Option<&FixedSizeListArray>

Downcast this to a [FixedSizeListArray] returning None if not possible
§

fn as_map_opt(&self) -> Option<&MapArray>

Downcast this to a [MapArray] returning None if not possible
§

fn as_dictionary_opt<K>(&self) -> Option<&DictionaryArray<K>>
where K: ArrowDictionaryKeyType,

Downcast this to a [DictionaryArray] returning None if not possible
§

fn as_any_dictionary_opt(&self) -> Option<&dyn AnyDictionaryArray>

Downcasts this to a [AnyDictionaryArray] returning None if not possible
§

fn as_run_opt<K>(&self) -> Option<&RunArray<K>>
where K: RunEndIndexType,

Downcast this to a [RunArray] returning None if not possible
§

fn as_string_opt<O>(&self) -> Option<&GenericByteArray<GenericStringType<O>>>
where O: OffsetSizeTrait,

Downcast this to a [GenericStringArray] returning None if not possible
§

fn as_boolean(&self) -> &BooleanArray

Downcast this to a [BooleanArray] panicking if not possible
§

fn as_primitive<T>(&self) -> &PrimitiveArray<T>
where T: ArrowPrimitiveType,

Downcast this to a [PrimitiveArray] panicking if not possible
§

fn as_bytes<T>(&self) -> &GenericByteArray<T>
where T: ByteArrayType,

Downcast this to a [GenericByteArray] panicking if not possible
§

fn as_string<O>(&self) -> &GenericByteArray<GenericStringType<O>>
where O: OffsetSizeTrait,

Downcast this to a [GenericStringArray] panicking if not possible
§

fn as_binary_opt<O>(&self) -> Option<&GenericByteArray<GenericBinaryType<O>>>
where O: OffsetSizeTrait,

Downcast this to a [GenericBinaryArray] returning None if not possible
§

fn as_binary<O>(&self) -> &GenericByteArray<GenericBinaryType<O>>
where O: OffsetSizeTrait,

Downcast this to a [GenericBinaryArray] panicking if not possible
§

fn as_string_view_opt(&self) -> Option<&GenericByteViewArray<StringViewType>>

Downcast this to a [StringViewArray] returning None if not possible
§

fn as_string_view(&self) -> &GenericByteViewArray<StringViewType>

Downcast this to a [StringViewArray] panicking if not possible
§

fn as_binary_view_opt(&self) -> Option<&GenericByteViewArray<BinaryViewType>>

Downcast this to a [BinaryViewArray] returning None if not possible
§

fn as_binary_view(&self) -> &GenericByteViewArray<BinaryViewType>

Downcast this to a [BinaryViewArray] panicking if not possible
§

fn as_byte_view<T>(&self) -> &GenericByteViewArray<T>
where T: ByteViewType,

Downcast this to a [GenericByteViewArray] panicking if not possible
§

fn as_struct(&self) -> &StructArray

Downcast this to a [StructArray] panicking if not possible
§

fn as_union(&self) -> &UnionArray

Downcast this to a [UnionArray] panicking if not possible
§

fn as_list<O>(&self) -> &GenericListArray<O>
where O: OffsetSizeTrait,

Downcast this to a [GenericListArray] panicking if not possible
§

fn as_list_view<O>(&self) -> &GenericListViewArray<O>
where O: OffsetSizeTrait,

Downcast this to a [GenericListViewArray] panicking if not possible
§

fn as_fixed_size_binary(&self) -> &FixedSizeBinaryArray

Downcast this to a [FixedSizeBinaryArray] panicking if not possible
§

fn as_fixed_size_list(&self) -> &FixedSizeListArray

Downcast this to a [FixedSizeListArray] panicking if not possible
§

fn as_map(&self) -> &MapArray

Downcast this to a [MapArray] panicking if not possible
§

fn as_dictionary<K>(&self) -> &DictionaryArray<K>
where K: ArrowDictionaryKeyType,

Downcast this to a [DictionaryArray] panicking if not possible
§

fn as_run<K>(&self) -> &RunArray<K>
where K: RunEndIndexType,

Downcast this to a [RunArray] panicking if not possible
§

fn as_any_dictionary(&self) -> &dyn AnyDictionaryArray

Downcasts this to a [AnyDictionaryArray] panicking if not possible
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impl<T> AsBacktrace for Arc<T>
where T: AsBacktrace,

§

fn as_backtrace(&self) -> Option<&Backtrace>

Retrieve the optional backtrace
1.64.0 · Source§

impl<T> AsFd for Arc<T>
where T: AsFd + ?Sized,

This impl allows implementing traits that require AsFd on Arc.

use std::net::UdpSocket;
use std::sync::Arc;

trait MyTrait: AsFd {}
impl MyTrait for Arc<UdpSocket> {}
impl MyTrait for Box<UdpSocket> {}
Source§

fn as_fd(&self) -> BorrowedFd<'_>

Borrows the file descriptor. Read more
1.63.0 · Source§

impl<T> AsRawFd for Arc<T>
where T: AsRawFd,

This impl allows implementing traits that require AsRawFd on Arc.

use std::net::UdpSocket;
use std::sync::Arc;
trait MyTrait: AsRawFd {
}
impl MyTrait for Arc<UdpSocket> {}
impl MyTrait for Box<UdpSocket> {}
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fn as_raw_fd(&self) -> i32

Extracts the raw file descriptor. Read more
1.5.0 · Source§

impl<T, A> AsRef<T> for Arc<T, A>
where A: Allocator, T: ?Sized,

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fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.
1.0.0 · Source§

impl<T, A> Borrow<T> for Arc<T, A>
where A: Allocator, T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
1.0.0 · Source§

impl<T, A> Clone for Arc<T, A>
where A: Allocator + Clone, T: ?Sized,

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fn clone(&self) -> Arc<T, A>

Makes a clone of the Arc pointer.

This creates another pointer to the same allocation, increasing the strong reference count.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

let _ = Arc::clone(&five);
1.0.0 · Source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
1.0.0 · Source§

impl<T, A> Debug for Arc<T, A>
where T: Debug + ?Sized, A: Allocator,

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fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more
1.80.0 · Source§

impl<T> Default for Arc<[T]>

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fn default() -> Arc<[T]>

Creates an empty [T] inside an Arc

This may or may not share an allocation with other Arcs.

1.80.0 · Source§

impl Default for Arc<CStr>

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fn default() -> Arc<CStr>

Creates an empty CStr inside an Arc

This may or may not share an allocation with other Arcs.

1.0.0 · Source§

impl<T> Default for Arc<T>
where T: Default,

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fn default() -> Arc<T>

Creates a new Arc<T>, with the Default value for T.

§Examples
use std::sync::Arc;

let x: Arc<i32> = Default::default();
assert_eq!(*x, 0);
1.80.0 · Source§

impl Default for Arc<str>

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fn default() -> Arc<str>

Creates an empty str inside an Arc

This may or may not share an allocation with other Arcs.

1.0.0 · Source§

impl<T, A> Deref for Arc<T, A>
where A: Allocator, T: ?Sized,

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type Target = T

The resulting type after dereferencing.
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fn deref(&self) -> &T

Dereferences the value.
1.0.0 · Source§

impl<T, A> Display for Arc<T, A>
where T: Display + ?Sized, A: Allocator,

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fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more
1.0.0 · Source§

impl<T, A> Drop for Arc<T, A>
where A: Allocator, T: ?Sized,

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fn drop(&mut self)

Drops the Arc.

This will decrement the strong reference count. If the strong reference count reaches zero then the only other references (if any) are Weak, so we drop the inner value.

§Examples
use std::sync::Arc;

struct Foo;

impl Drop for Foo {
    fn drop(&mut self) {
        println!("dropped!");
    }
}

let foo  = Arc::new(Foo);
let foo2 = Arc::clone(&foo);

drop(foo);    // Doesn't print anything
drop(foo2);   // Prints "dropped!"
1.52.0 · Source§

impl<T> Error for Arc<T>
where T: Error + ?Sized,

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fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()
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fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting
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fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any. Read more
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fn provide<'a>(&'a self, req: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)
Provides type-based access to context intended for error reports. Read more
1.21.0 · Source§

impl<T> From<&[T]> for Arc<[T]>
where T: Clone,

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fn from(v: &[T]) -> Arc<[T]>

Allocates a reference-counted slice and fills it by cloning v’s items.

§Example
let original: &[i32] = &[1, 2, 3];
let shared: Arc<[i32]> = Arc::from(original);
assert_eq!(&[1, 2, 3], &shared[..]);
1.24.0 · Source§

impl From<&CStr> for Arc<CStr>

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fn from(s: &CStr) -> Arc<CStr>

Converts a &CStr into a Arc<CStr>, by copying the contents into a newly allocated Arc.

1.24.0 · Source§

impl From<&OsStr> for Arc<OsStr>

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fn from(s: &OsStr) -> Arc<OsStr>

Copies the string into a newly allocated Arc<OsStr>.

1.24.0 · Source§

impl From<&Path> for Arc<Path>

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fn from(s: &Path) -> Arc<Path>

Converts a Path into an Arc by copying the Path data into a new Arc buffer.

1.84.0 · Source§

impl<T> From<&mut [T]> for Arc<[T]>
where T: Clone,

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fn from(v: &mut [T]) -> Arc<[T]>

Allocates a reference-counted slice and fills it by cloning v’s items.

§Example
let mut original = [1, 2, 3];
let original: &mut [i32] = &mut original;
let shared: Arc<[i32]> = Arc::from(original);
assert_eq!(&[1, 2, 3], &shared[..]);
1.84.0 · Source§

impl From<&mut CStr> for Arc<CStr>

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fn from(s: &mut CStr) -> Arc<CStr>

Converts a &mut CStr into a Arc<CStr>, by copying the contents into a newly allocated Arc.

1.84.0 · Source§

impl From<&mut OsStr> for Arc<OsStr>

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fn from(s: &mut OsStr) -> Arc<OsStr>

Copies the string into a newly allocated Arc<OsStr>.

1.84.0 · Source§

impl From<&mut Path> for Arc<Path>

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fn from(s: &mut Path) -> Arc<Path>

Converts a Path into an Arc by copying the Path data into a new Arc buffer.

1.84.0 · Source§

impl From<&mut str> for Arc<str>

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fn from(v: &mut str) -> Arc<str>

Allocates a reference-counted str and copies v into it.

§Example
let mut original = String::from("eggplant");
let original: &mut str = &mut original;
let shared: Arc<str> = Arc::from(original);
assert_eq!("eggplant", &shared[..]);
1.21.0 · Source§

impl From<&str> for Arc<str>

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fn from(v: &str) -> Arc<str>

Allocates a reference-counted str and copies v into it.

§Example
let shared: Arc<str> = Arc::from("eggplant");
assert_eq!("eggplant", &shared[..]);
1.74.0 · Source§

impl<T, const N: usize> From<[T; N]> for Arc<[T]>

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fn from(v: [T; N]) -> Arc<[T]>

Converts a [T; N] into an Arc<[T]>.

The conversion moves the array into a newly allocated Arc.

§Example
let original: [i32; 3] = [1, 2, 3];
let shared: Arc<[i32]> = Arc::from(original);
assert_eq!(&[1, 2, 3], &shared[..]);
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impl From<Arc<[u8]>> for Arc<ByteStr>

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fn from(s: Arc<[u8]>) -> Arc<ByteStr>

Converts to this type from the input type.
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impl From<Arc<ByteStr>> for Arc<[u8]>

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fn from(s: Arc<ByteStr>) -> Arc<[u8]>

Converts to this type from the input type.
1.51.0 · Source§

impl<W> From<Arc<W>> for Waker
where W: Wake + Send + Sync + 'static,

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fn from(waker: Arc<W>) -> Waker

Use a Wake-able type as a Waker.

No heap allocations or atomic operations are used for this conversion.

1.62.0 · Source§

impl From<Arc<str>> for Arc<[u8]>

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fn from(rc: Arc<str>) -> Arc<[u8]>

Converts an atomically reference-counted string slice into a byte slice.

§Example
let string: Arc<str> = Arc::from("eggplant");
let bytes: Arc<[u8]> = Arc::from(string);
assert_eq!("eggplant".as_bytes(), bytes.as_ref());
1.21.0 · Source§

impl<T, A> From<Box<T, A>> for Arc<T, A>
where A: Allocator, T: ?Sized,

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fn from(v: Box<T, A>) -> Arc<T, A>

Move a boxed object to a new, reference-counted allocation.

§Example
let unique: Box<str> = Box::from("eggplant");
let shared: Arc<str> = Arc::from(unique);
assert_eq!("eggplant", &shared[..]);
1.24.0 · Source§

impl From<CString> for Arc<CStr>

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fn from(s: CString) -> Arc<CStr>

Converts a CString into an Arc<CStr> by moving the CString data into a new Arc buffer.

1.45.0 · Source§

impl<'a, B> From<Cow<'a, B>> for Arc<B>
where B: ToOwned + ?Sized, Arc<B>: From<&'a B> + From<<B as ToOwned>::Owned>,

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fn from(cow: Cow<'a, B>) -> Arc<B>

Creates an atomically reference-counted pointer from a clone-on-write pointer by copying its content.

§Example
let cow: Cow<'_, str> = Cow::Borrowed("eggplant");
let shared: Arc<str> = Arc::from(cow);
assert_eq!("eggplant", &shared[..]);
1.24.0 · Source§

impl From<OsString> for Arc<OsStr>

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fn from(s: OsString) -> Arc<OsStr>

Converts an OsString into an Arc<OsStr> by moving the OsString data into a new Arc buffer.

1.24.0 · Source§

impl From<PathBuf> for Arc<Path>

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fn from(s: PathBuf) -> Arc<Path>

Converts a PathBuf into an Arc<Path> by moving the PathBuf data into a new Arc buffer.

1.21.0 · Source§

impl From<String> for Arc<str>

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fn from(v: String) -> Arc<str>

Allocates a reference-counted str and copies v into it.

§Example
let unique: String = "eggplant".to_owned();
let shared: Arc<str> = Arc::from(unique);
assert_eq!("eggplant", &shared[..]);
1.6.0 · Source§

impl<T> From<T> for Arc<T>

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fn from(t: T) -> Arc<T>

Converts a T into an Arc<T>

The conversion moves the value into a newly allocated Arc. It is equivalent to calling Arc::new(t).

§Example
let x = 5;
let arc = Arc::new(5);

assert_eq!(Arc::from(x), arc);
1.21.0 · Source§

impl<T, A> From<Vec<T, A>> for Arc<[T], A>
where A: Allocator + Clone,

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fn from(v: Vec<T, A>) -> Arc<[T], A>

Allocates a reference-counted slice and moves v’s items into it.

§Example
let unique: Vec<i32> = vec![1, 2, 3];
let shared: Arc<[i32]> = Arc::from(unique);
assert_eq!(&[1, 2, 3], &shared[..]);
1.37.0 · Source§

impl<T> FromIterator<T> for Arc<[T]>

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fn from_iter<I>(iter: I) -> Arc<[T]>
where I: IntoIterator<Item = T>,

Takes each element in the Iterator and collects it into an Arc<[T]>.

§Performance characteristics
§The general case

In the general case, collecting into Arc<[T]> is done by first collecting into a Vec<T>. That is, when writing the following:

let evens: Arc<[u8]> = (0..10).filter(|&x| x % 2 == 0).collect();

this behaves as if we wrote:

let evens: Arc<[u8]> = (0..10).filter(|&x| x % 2 == 0)
    .collect::<Vec<_>>() // The first set of allocations happens here.
    .into(); // A second allocation for `Arc<[T]>` happens here.

This will allocate as many times as needed for constructing the Vec<T> and then it will allocate once for turning the Vec<T> into the Arc<[T]>.

§Iterators of known length

When your Iterator implements TrustedLen and is of an exact size, a single allocation will be made for the Arc<[T]>. For example:

let evens: Arc<[u8]> = (0..10).collect(); // Just a single allocation happens here.
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impl<T> FromParallelIterator<T> for Arc<[T]>
where T: Send,

Collects items from a parallel iterator into an atomically-reference-counted slice.

§

fn from_par_iter<I>(par_iter: I) -> Arc<[T]>
where I: IntoParallelIterator<Item = T>,

Creates an instance of the collection from the parallel iterator par_iter. Read more
§

impl<T> GenerateImplicitData for Arc<T>
where T: GenerateImplicitData,

§

fn generate() -> Arc<T>

Build the data.
§

fn generate_with_source(source: &dyn Error) -> Arc<T>
where Arc<T>: Sized,

Build the data using the given source
1.0.0 · Source§

impl<T, A> Hash for Arc<T, A>
where T: Hash + ?Sized, A: Allocator,

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fn hash<H>(&self, state: &mut H)
where H: Hasher,

Feeds this value into the given Hasher. Read more
1.3.0 · Source§

fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl<Sp> LocalSpawn for Arc<Sp>
where Sp: LocalSpawn + ?Sized,

§

fn spawn_local_obj( &self, future: LocalFutureObj<'static, ()>, ) -> Result<(), SpawnError>

Spawns a future that will be run to completion. Read more
§

fn status_local(&self) -> Result<(), SpawnError>

Determines whether the executor is able to spawn new tasks. Read more
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impl<T> Log for Arc<T>
where T: Log + ?Sized,

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fn enabled(&self, metadata: &Metadata<'_>) -> bool

Determines if a log message with the specified metadata would be logged. Read more
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fn log(&self, record: &Record<'_>)

Logs the Record. Read more
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fn flush(&self)

Flushes any buffered records. Read more
1.0.0 · Source§

impl<T, A> Ord for Arc<T, A>
where T: Ord + ?Sized, A: Allocator,

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fn cmp(&self, other: &Arc<T, A>) -> Ordering

Comparison for two Arcs.

The two are compared by calling cmp() on their inner values.

§Examples
use std::sync::Arc;
use std::cmp::Ordering;

let five = Arc::new(5);

assert_eq!(Ordering::Less, five.cmp(&Arc::new(6)));
1.21.0 · Source§

fn max(self, other: Self) -> Self
where Self: Sized,

Compares and returns the maximum of two values. Read more
1.21.0 · Source§

fn min(self, other: Self) -> Self
where Self: Sized,

Compares and returns the minimum of two values. Read more
1.50.0 · Source§

fn clamp(self, min: Self, max: Self) -> Self
where Self: Sized,

Restrict a value to a certain interval. Read more
1.0.0 · Source§

impl<T, A> PartialEq for Arc<T, A>
where T: PartialEq + ?Sized, A: Allocator,

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fn eq(&self, other: &Arc<T, A>) -> bool

Equality for two Arcs.

Two Arcs are equal if their inner values are equal, even if they are stored in different allocation.

If T also implements Eq (implying reflexivity of equality), two Arcs that point to the same allocation are always equal.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five == Arc::new(5));
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fn ne(&self, other: &Arc<T, A>) -> bool

Inequality for two Arcs.

Two Arcs are not equal if their inner values are not equal.

If T also implements Eq (implying reflexivity of equality), two Arcs that point to the same value are always equal.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five != Arc::new(6));
1.0.0 · Source§

impl<T, A> PartialOrd for Arc<T, A>
where T: PartialOrd + ?Sized, A: Allocator,

Source§

fn partial_cmp(&self, other: &Arc<T, A>) -> Option<Ordering>

Partial comparison for two Arcs.

The two are compared by calling partial_cmp() on their inner values.

§Examples
use std::sync::Arc;
use std::cmp::Ordering;

let five = Arc::new(5);

assert_eq!(Some(Ordering::Less), five.partial_cmp(&Arc::new(6)));
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fn lt(&self, other: &Arc<T, A>) -> bool

Less-than comparison for two Arcs.

The two are compared by calling < on their inner values.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five < Arc::new(6));
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fn le(&self, other: &Arc<T, A>) -> bool

‘Less than or equal to’ comparison for two Arcs.

The two are compared by calling <= on their inner values.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five <= Arc::new(5));
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fn gt(&self, other: &Arc<T, A>) -> bool

Greater-than comparison for two Arcs.

The two are compared by calling > on their inner values.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five > Arc::new(4));
Source§

fn ge(&self, other: &Arc<T, A>) -> bool

‘Greater than or equal to’ comparison for two Arcs.

The two are compared by calling >= on their inner values.

§Examples
use std::sync::Arc;

let five = Arc::new(5);

assert!(five >= Arc::new(5));
1.0.0 · Source§

impl<T, A> Pointer for Arc<T, A>
where A: Allocator, T: ?Sized,

Source§

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more
1.73.0 · Source§

impl Read for Arc<File>

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fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error>

Pull some bytes from this source into the specified buffer, returning how many bytes were read. Read more
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fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers. Read more
Source§

fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)
Pull some bytes from this source into the specified buffer. Read more
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fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)
Determines if this Reader has an efficient read_vectored implementation. Read more
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fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf. Read more
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fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf. Read more
1.6.0 · Source§

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf. Read more
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fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)
Reads the exact number of bytes required to fill cursor. Read more
1.0.0 · Source§

fn by_ref(&mut self) -> &mut Self
where Self: Sized,

Creates a “by reference” adaptor for this instance of Read. Read more
1.0.0 · Source§

fn bytes(self) -> Bytes<Self>
where Self: Sized,

Transforms this Read instance to an Iterator over its bytes. Read more
1.0.0 · Source§

fn chain<R>(self, next: R) -> Chain<Self, R>
where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another. Read more
1.0.0 · Source§

fn take(self, limit: u64) -> Take<Self>
where Self: Sized,

Creates an adapter which will read at most limit bytes from it. Read more
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impl RowGroups for Arc<dyn FileReader>

§

fn num_rows(&self) -> usize

Get the number of rows in this collection
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fn column_chunks( &self, column_index: usize, ) -> Result<Box<dyn PageIterator<Item = Result<Box<dyn PageReader<Item = Result<Page, ParquetError>>>, ParquetError>>>, ParquetError>

Returns a [PageIterator] for all pages in the specified column chunk across all row groups in this collection.
1.73.0 · Source§

impl Seek for Arc<File>

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fn seek(&mut self, pos: SeekFrom) -> Result<u64, Error>

Seek to an offset, in bytes, in a stream. Read more
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fn stream_len(&mut self) -> Result<u64, Error>

🔬This is a nightly-only experimental API. (seek_stream_len)
Returns the length of this stream (in bytes). Read more
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fn stream_position(&mut self) -> Result<u64, Error>

Returns the current seek position from the start of the stream. Read more
1.55.0 · Source§

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream. Read more
1.80.0 · Source§

fn seek_relative(&mut self, offset: i64) -> Result<(), Error>

Seeks relative to the current position. Read more
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impl<Sp> Spawn for Arc<Sp>
where Sp: Spawn + ?Sized,

§

fn spawn_obj(&self, future: FutureObj<'static, ()>) -> Result<(), SpawnError>

Spawns a future that will be run to completion. Read more
§

fn status(&self) -> Result<(), SpawnError>

Determines whether the executor is able to spawn new tasks. Read more
§

impl<S> Subscriber for Arc<S>
where S: Subscriber + ?Sized,

§

fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest

Registers a new callsite with this subscriber, returning whether or not the subscriber is interested in being notified about the callsite. Read more
§

fn enabled(&self, metadata: &Metadata<'_>) -> bool

Returns true if a span or event with the specified metadata would be recorded. Read more
§

fn max_level_hint(&self) -> Option<LevelFilter>

Returns the highest verbosity level that this Subscriber will enable, or None, if the subscriber does not implement level-based filtering or chooses not to implement this method. Read more
§

fn new_span(&self, span: &Attributes<'_>) -> Id

Visit the construction of a new span, returning a new span ID for the span being constructed. Read more
§

fn record(&self, span: &Id, values: &Record<'_>)

Record a set of values on a span. Read more
§

fn record_follows_from(&self, span: &Id, follows: &Id)

Adds an indication that span follows from the span with the id follows. Read more
§

fn event_enabled(&self, event: &Event<'_>) -> bool

Determine if an [Event] should be recorded. Read more
§

fn event(&self, event: &Event<'_>)

Records that an Event has occurred. Read more
§

fn enter(&self, span: &Id)

Records that a span has been entered. Read more
§

fn exit(&self, span: &Id)

Records that a span has been exited. Read more
§

fn clone_span(&self, id: &Id) -> Id

Notifies the subscriber that a span ID has been cloned. Read more
§

fn try_close(&self, id: Id) -> bool

Notifies the subscriber that a span ID has been dropped, and returns true if there are now 0 IDs that refer to that span. Read more
§

fn drop_span(&self, id: Id)

👎Deprecated since 0.1.2: use Subscriber::try_close instead
This method is deprecated. Read more
§

fn current_span(&self) -> Current

Returns a type representing this subscriber’s view of the current span. Read more
§

unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()>

If self is the same type as the provided TypeId, returns an untyped *const pointer to that type. Otherwise, returns None. Read more
§

fn on_register_dispatch(&self, subscriber: &Dispatch)

Invoked when this subscriber becomes a [Dispatch]. Read more
1.43.0 · Source§

impl<T, A, const N: usize> TryFrom<Arc<[T], A>> for Arc<[T; N], A>
where A: Allocator,

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type Error = Arc<[T], A>

The type returned in the event of a conversion error.
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fn try_from( boxed_slice: Arc<[T], A>, ) -> Result<Arc<[T; N], A>, <Arc<[T; N], A> as TryFrom<Arc<[T], A>>>::Error>

Performs the conversion.
1.73.0 · Source§

impl Write for Arc<File>

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fn write(&mut self, buf: &[u8]) -> Result<usize, Error>

Writes a buffer into this writer, returning how many bytes were written. Read more
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fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers. Read more
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fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)
Determines if this Writer has an efficient write_vectored implementation. Read more
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fn flush(&mut self) -> Result<(), Error>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination. Read more
1.0.0 · Source§

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer. Read more
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fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)
Attempts to write multiple buffers into this writer. Read more
1.0.0 · Source§

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered. Read more
1.0.0 · Source§

fn by_ref(&mut self) -> &mut Self
where Self: Sized,

Creates a “by reference” adapter for this instance of Write. Read more
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impl<'a, T> Writeable for Arc<T>
where T: Writeable + ?Sized,

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fn write_to<W>(&self, sink: &mut W) -> Result<(), Error>
where W: Write + ?Sized,

Writes a string to the given sink. Errors from the sink are bubbled up. The default implementation delegates to write_to_parts, and discards any Part annotations.
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fn write_to_parts<W>(&self, sink: &mut W) -> Result<(), Error>
where W: PartsWrite + ?Sized,

Write bytes and Part annotations to the given sink. Errors from the sink are bubbled up. The default implementation delegates to write_to, and doesn’t produce any Part annotations.
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fn writeable_length_hint(&self) -> LengthHint

Returns a hint for the number of UTF-8 bytes that will be written to the sink. Read more
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fn write_to_string(&self) -> Cow<'_, str>

Creates a new String with the data from this Writeable. Like ToString, but smaller and faster. Read more
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impl<T> CartablePointerLike for Arc<T>

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impl<T> CloneStableDeref for Arc<T>
where T: ?Sized,

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impl<T> CloneableCart for Arc<T>
where T: ?Sized,

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impl<T> CloneableCartablePointerLike for Arc<T>

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impl<T, U, A> CoerceUnsized<Arc<U, A>> for Arc<T, A>
where T: Unsize<U> + ?Sized, A: Allocator, U: ?Sized,

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impl<T, A> DerefPure for Arc<T, A>
where A: Allocator, T: ?Sized,

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impl<T, U> DispatchFromDyn<Arc<U>> for Arc<T>
where T: Unsize<U> + ?Sized, U: ?Sized,

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impl<T, A> Eq for Arc<T, A>
where T: Eq + ?Sized, A: Allocator,

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impl<T, A> PinCoerceUnsized for Arc<T, A>
where A: Allocator, T: ?Sized,

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impl<T, A> Send for Arc<T, A>
where T: Sync + Send + ?Sized, A: Allocator + Send,

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impl<T> StableDeref for Arc<T>
where T: ?Sized,

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impl<T, A> Sync for Arc<T, A>
where T: Sync + Send + ?Sized, A: Allocator + Sync,

1.33.0 · Source§

impl<T, A> Unpin for Arc<T, A>
where A: Allocator, T: ?Sized,

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impl<T, A> UnwindSafe for Arc<T, A>

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impl<T, A> UseCloned for Arc<T, A>
where A: Allocator + Clone, T: ?Sized,

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impl<T, A> Freeze for Arc<T, A>
where A: Freeze, T: ?Sized,

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impl<T, A> RefUnwindSafe for Arc<T, A>

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> AsErrorSource for T
where T: Error + 'static,

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fn as_error_source(&self) -> &(dyn Error + 'static)

For maximum effectiveness, this needs to be called as a method to benefit from Rust’s automatic dereferencing of method receivers.
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<Q, K> Comparable<K> for Q
where Q: Ord + ?Sized, K: Borrow<Q> + ?Sized,

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fn compare(&self, key: &K) -> Ordering

Compare self to key and return their ordering.
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impl<T> Datum for T
where T: Array,

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fn get(&self) -> (&dyn Array, bool)

Returns the value for this [Datum] and a boolean indicating if the value is scalar
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impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

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fn equivalent(&self, key: &K) -> bool

Compare self to key and return true if they are equal.
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impl<R> FixedIntReader for R
where R: Read,

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fn read_fixedint<FI>(&mut self) -> Result<FI, Error>
where FI: FixedInt,

Read a fixed integer from a reader. How many bytes are read depends on FI. Read more
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impl<W> FixedIntWriter for W
where W: Write,

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fn write_fixedint<FI>(&mut self, n: FI) -> Result<usize, Error>
where FI: FixedInt,

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impl<T> From<!> for T

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fn from(t: !) -> T

Converts to this type from the input type.
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T> Instrument for T

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fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided [Span], returning an Instrumented wrapper. Read more
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fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more
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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> IntoEither for T

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fn into_either(self, into_left: bool) -> Either<Self, Self>

Converts self into a Left variant of Either<Self, Self> if into_left is true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
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fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
where F: FnOnce(&Self) -> bool,

Converts self into a Left variant of Either<Self, Self> if into_left(&self) returns true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
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impl<Sp> LocalSpawnExt for Sp
where Sp: LocalSpawn + ?Sized,

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fn spawn_local<Fut>(&self, future: Fut) -> Result<(), SpawnError>
where Fut: Future<Output = ()> + 'static,

Spawns a task that polls the given future with output () to completion. Read more
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impl<T> Pointable for T

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const ALIGN: usize

The alignment of pointer.
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type Init = T

The type for initializers.
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unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more
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unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more
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unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

Mutably dereferences the given pointer. Read more
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unsafe fn drop(ptr: usize)

Drops the object pointed to by the given pointer. Read more
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impl<R> ReadBytesExt for R
where R: Read + ?Sized,

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fn read_u8(&mut self) -> Result<u8, Error>

Reads an unsigned 8 bit integer from the underlying reader. Read more
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fn read_i8(&mut self) -> Result<i8, Error>

Reads a signed 8 bit integer from the underlying reader. Read more
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fn read_u16<T>(&mut self) -> Result<u16, Error>
where T: ByteOrder,

Reads an unsigned 16 bit integer from the underlying reader. Read more
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fn read_i16<T>(&mut self) -> Result<i16, Error>
where T: ByteOrder,

Reads a signed 16 bit integer from the underlying reader. Read more
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fn read_u24<T>(&mut self) -> Result<u32, Error>
where T: ByteOrder,

Reads an unsigned 24 bit integer from the underlying reader. Read more
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fn read_i24<T>(&mut self) -> Result<i32, Error>
where T: ByteOrder,

Reads a signed 24 bit integer from the underlying reader. Read more
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fn read_u32<T>(&mut self) -> Result<u32, Error>
where T: ByteOrder,

Reads an unsigned 32 bit integer from the underlying reader. Read more
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fn read_i32<T>(&mut self) -> Result<i32, Error>
where T: ByteOrder,

Reads a signed 32 bit integer from the underlying reader. Read more
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fn read_u48<T>(&mut self) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned 48 bit integer from the underlying reader. Read more
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fn read_i48<T>(&mut self) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed 48 bit integer from the underlying reader. Read more
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fn read_u64<T>(&mut self) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned 64 bit integer from the underlying reader. Read more
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fn read_i64<T>(&mut self) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed 64 bit integer from the underlying reader. Read more
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fn read_u128<T>(&mut self) -> Result<u128, Error>
where T: ByteOrder,

Reads an unsigned 128 bit integer from the underlying reader. Read more
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fn read_i128<T>(&mut self) -> Result<i128, Error>
where T: ByteOrder,

Reads a signed 128 bit integer from the underlying reader. Read more
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fn read_uint<T>(&mut self, nbytes: usize) -> Result<u64, Error>
where T: ByteOrder,

Reads an unsigned n-bytes integer from the underlying reader. Read more
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fn read_int<T>(&mut self, nbytes: usize) -> Result<i64, Error>
where T: ByteOrder,

Reads a signed n-bytes integer from the underlying reader. Read more
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fn read_uint128<T>(&mut self, nbytes: usize) -> Result<u128, Error>
where T: ByteOrder,

Reads an unsigned n-bytes integer from the underlying reader.
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fn read_int128<T>(&mut self, nbytes: usize) -> Result<i128, Error>
where T: ByteOrder,

Reads a signed n-bytes integer from the underlying reader.
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fn read_f32<T>(&mut self) -> Result<f32, Error>
where T: ByteOrder,

Reads a IEEE754 single-precision (4 bytes) floating point number from the underlying reader. Read more
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fn read_f64<T>(&mut self) -> Result<f64, Error>
where T: ByteOrder,

Reads a IEEE754 double-precision (8 bytes) floating point number from the underlying reader. Read more
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fn read_u16_into<T>(&mut self, dst: &mut [u16]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 16 bit integers from the underlying reader. Read more
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fn read_u32_into<T>(&mut self, dst: &mut [u32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 32 bit integers from the underlying reader. Read more
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fn read_u64_into<T>(&mut self, dst: &mut [u64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 64 bit integers from the underlying reader. Read more
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fn read_u128_into<T>(&mut self, dst: &mut [u128]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of unsigned 128 bit integers from the underlying reader. Read more
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fn read_i8_into(&mut self, dst: &mut [i8]) -> Result<(), Error>

Reads a sequence of signed 8 bit integers from the underlying reader. Read more
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fn read_i16_into<T>(&mut self, dst: &mut [i16]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 16 bit integers from the underlying reader. Read more
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fn read_i32_into<T>(&mut self, dst: &mut [i32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 32 bit integers from the underlying reader. Read more
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fn read_i64_into<T>(&mut self, dst: &mut [i64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 64 bit integers from the underlying reader. Read more
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fn read_i128_into<T>(&mut self, dst: &mut [i128]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of signed 128 bit integers from the underlying reader. Read more
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fn read_f32_into<T>(&mut self, dst: &mut [f32]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of IEEE754 single-precision (4 bytes) floating point numbers from the underlying reader. Read more
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fn read_f32_into_unchecked<T>(&mut self, dst: &mut [f32]) -> Result<(), Error>
where T: ByteOrder,

👎Deprecated since 1.2.0: please use read_f32_into instead
DEPRECATED. Read more
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fn read_f64_into<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

Reads a sequence of IEEE754 double-precision (8 bytes) floating point numbers from the underlying reader. Read more
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fn read_f64_into_unchecked<T>(&mut self, dst: &mut [f64]) -> Result<(), Error>
where T: ByteOrder,

👎Deprecated since 1.2.0: please use read_f64_into instead
DEPRECATED. Read more
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impl<P, T> Receiver for P
where P: Deref<Target = T> + ?Sized, T: ?Sized,

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type Target = T

🔬This is a nightly-only experimental API. (arbitrary_self_types)
The target type on which the method may be called.
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impl<T> Same for T

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type Output = T

Should always be Self
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impl<Sp> SpawnExt for Sp
where Sp: Spawn + ?Sized,

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fn spawn<Fut>(&self, future: Fut) -> Result<(), SpawnError>
where Fut: Future<Output = ()> + Send + 'static,

Spawns a task that polls the given future with output () to completion. Read more
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impl<SS, SP> SupersetOf<SS> for SP
where SS: SubsetOf<SP>,

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fn to_subset(&self) -> Option<SS>

The inverse inclusion map: attempts to construct self from the equivalent element of its superset. Read more
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fn is_in_subset(&self) -> bool

Checks if self is actually part of its subset T (and can be converted to it).
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fn to_subset_unchecked(&self) -> SS

Use with care! Same as self.to_subset but without any property checks. Always succeeds.
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fn from_subset(element: &SS) -> SP

The inclusion map: converts self to the equivalent element of its superset.
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impl<T> ToHex for T
where T: AsRef<[u8]>,

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fn encode_hex<U>(&self) -> U
where U: FromIterator<char>,

Encode the hex strict representing self into the result. Lower case letters are used (e.g. f9b4ca)
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fn encode_hex_upper<U>(&self) -> U
where U: FromIterator<char>,

Encode the hex strict representing self into the result. Upper case letters are used (e.g. F9B4CA)
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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T> ToString for T
where T: Display + ?Sized,

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fn to_string(&self) -> String

Converts the given value to a String. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<V, T> VZip<V> for T
where V: MultiLane<T>,

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fn vzip(self) -> V

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impl<R> VarIntReader for R
where R: Read,

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fn read_varint<VI>(&mut self) -> Result<VI, Error>
where VI: VarInt,

Returns either the decoded integer, or an error. Read more
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impl<Inner> VarIntWriter for Inner
where Inner: Write,

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fn write_varint<VI>(&mut self, n: VI) -> Result<usize, Error>
where VI: VarInt,

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impl<T> WithSubscriber for T

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fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a [WithDispatch] wrapper. Read more
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fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a [WithDispatch] wrapper. Read more
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impl<W> WriteBytesExt for W
where W: Write + ?Sized,

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fn write_u8(&mut self, n: u8) -> Result<(), Error>

Writes an unsigned 8 bit integer to the underlying writer. Read more
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fn write_i8(&mut self, n: i8) -> Result<(), Error>

Writes a signed 8 bit integer to the underlying writer. Read more
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fn write_u16<T>(&mut self, n: u16) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 16 bit integer to the underlying writer. Read more
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fn write_i16<T>(&mut self, n: i16) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 16 bit integer to the underlying writer. Read more
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fn write_u24<T>(&mut self, n: u32) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 24 bit integer to the underlying writer. Read more
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fn write_i24<T>(&mut self, n: i32) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 24 bit integer to the underlying writer. Read more
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fn write_u32<T>(&mut self, n: u32) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 32 bit integer to the underlying writer. Read more
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fn write_i32<T>(&mut self, n: i32) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 32 bit integer to the underlying writer. Read more
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fn write_u48<T>(&mut self, n: u64) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 48 bit integer to the underlying writer. Read more
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fn write_i48<T>(&mut self, n: i64) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 48 bit integer to the underlying writer. Read more
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fn write_u64<T>(&mut self, n: u64) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 64 bit integer to the underlying writer. Read more
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fn write_i64<T>(&mut self, n: i64) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 64 bit integer to the underlying writer. Read more
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fn write_u128<T>(&mut self, n: u128) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned 128 bit integer to the underlying writer.
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fn write_i128<T>(&mut self, n: i128) -> Result<(), Error>
where T: ByteOrder,

Writes a signed 128 bit integer to the underlying writer.
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fn write_uint<T>(&mut self, n: u64, nbytes: usize) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned n-bytes integer to the underlying writer. Read more
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fn write_int<T>(&mut self, n: i64, nbytes: usize) -> Result<(), Error>
where T: ByteOrder,

Writes a signed n-bytes integer to the underlying writer. Read more
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fn write_uint128<T>(&mut self, n: u128, nbytes: usize) -> Result<(), Error>
where T: ByteOrder,

Writes an unsigned n-bytes integer to the underlying writer. Read more
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fn write_int128<T>(&mut self, n: i128, nbytes: usize) -> Result<(), Error>
where T: ByteOrder,

Writes a signed n-bytes integer to the underlying writer. Read more
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fn write_f32<T>(&mut self, n: f32) -> Result<(), Error>
where T: ByteOrder,

Writes a IEEE754 single-precision (4 bytes) floating point number to the underlying writer. Read more
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fn write_f64<T>(&mut self, n: f64) -> Result<(), Error>
where T: ByteOrder,

Writes a IEEE754 double-precision (8 bytes) floating point number to the underlying writer. Read more
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impl<T> Allocation for T
where T: RefUnwindSafe + Send + Sync,

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impl<T> ErasedDestructor for T
where T: 'static,

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impl<T> Scalar for T
where T: 'static + Clone + PartialEq + Debug,

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impl<T> TReadTransport for T
where T: Read,

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impl<T> TWriteTransport for T
where T: Write,