Repository: tokio-rs/tokio
File: tokio/src/runtime/task/id.rs (Rust)

Code before:
use crate::runtime::context;

use std::{fmt, num::NonZeroU64};

/// An opaque ID that uniquely identifies a task relative to all other currently
/// running tasks.
///
/// A task's ID may be re-used for another task only once *both* of the
/// following happen:
/// 1. The task itself exits.
/// 2. The task's [`JoinHandle`](crate::task::JoinHandle) is either dropped, or
///    joined on (for example, by `await`ing it to completion).
///
/// # Notes
///
/// - Task IDs are *not* sequential, and do not indicate the order in which
///   tasks are spawned, what runtime a task is spawned on, or any other data.
/// - Holding an [`AbortHandle`](crate::task::AbortHandle) alone does not
///   prevent a completed task's ID from being re-used.
/// - The task ID of the currently running task can be obtained from inside the
///   task via the [`task::try_id()`](crate::task::try_id()) and
///   [`task::id()`](crate::task::id()) functions and from outside the task via
///   the [`JoinHandle::id()`](crate::task::JoinHandle::id()) function.
#[cfg_attr(docsrs, doc(cfg(all(feature = "rt"))))]
#[derive(Clone, Copy, Debug, Hash, Eq, PartialEq, PartialOrd, Ord)]
pub struct Id(pub(crate) NonZeroU64);

/// Returns the [`Id`] of the currently running task.
///
/// # Panics
///
/// This function panics if called from outside a task. Please note that calls
/// to `block_on` do not have task IDs, so the method will panic if called from
/// within a call to `block_on`. For a version of this function that doesn't
/// panic, see [`task::try_id()`](crate::runtime::task::try_id()).
///
/// [task ID]: crate::task::Id
#[track_caller]

Review comment (suggestion):
```suggestion
/// 2. There is no active [`JoinHandle`] associated with this task.
///
/// The following situations are considered to have active [`JoinHandle`].
///
/// - You are explicitly holding an [`JoinHandle`] or [`AbortHandle`] or `tokio_util::task::AbortOnDropHandle`.
/// - Task is still tracked by [`JoinSet`] or `tokio_util::task::JoinMap`.
///
/// [`JoinHandle`]: crate::task::JoinHandle
/// [`AbortHandle`]: crate::task::AbortHandle
/// [`JoinSet`]: crate::task::Joinset
```

Code after:
use crate::runtime::context;

use std::{fmt, num::NonZeroU64};

/// An opaque ID that uniquely identifies a task relative to all other currently
/// running tasks.
///
/// A task's ID may be re-used for another task only once *both* of the
/// following happen:
/// 1. The task itself exits.
/// 2. There is no active [`JoinHandle`] associated with this task.
///
/// A [`JoinHandle`] is considered active in the following situations:
/// - You are explicitly holding a [`JoinHandle`], [`AbortHandle`], or
///   `tokio_util::task::AbortOnDropHandle`.
/// - The task is being tracked by a [`JoinSet`] or `tokio_util::task::JoinMap`.
///
/// # Notes
///
/// - Task IDs are *not* sequential, and do not indicate the order in which
///   tasks are spawned, what runtime a task is spawned on, or any other data.
/// - The task ID of the currently running task can be obtained from inside the
///   task via the [`task::try_id()`](crate::task::try_id()) and
///   [`task::id()`](crate::task::id()) functions and from outside the task via
///   the [`JoinHandle::id()`](crate::task::JoinHandle::id()) function.
///
/// [`JoinHandle`]: crate::task::JoinHandle
/// [`AbortHandle`]: crate::task::AbortHandle
/// [`JoinSet`]: crate::task::JoinSet
#[cfg_attr(docsrs, doc(cfg(all(feature = "rt"))))]
#[derive(Clone, Copy, Debug, Hash, Eq, PartialEq, PartialOrd, Ord)]
pub struct Id(pub(crate) NonZeroU64);

/// Returns the [`Id`] of the currently running task.
///
/// # Panics
///
/// This function panics if called from outside a task. Please note that calls