package wasi:clocks@0.2.0;
/// WASI Monotonic Clock is a clock API intended to let users measure elapsed
/// time.
///
/// It is intended to be portable at least between Unix-family platforms and
/// Windows.
///
/// A monotonic clock is a clock which has an unspecified initial value, and
/// successive reads of the clock will produce non-decreasing values.
///
/// It is intended for measuring elapsed time.
interface monotonic-clock {
    use wasi:io/poll@0.2.0.{pollable};

    /// An instant in time, in nanoseconds. An instant is relative to an
    /// unspecified initial value, and can only be compared to instances from
    /// the same monotonic-clock.
    type instant = u64;

    /// A duration of time, in nanoseconds.
    type duration = u64;

    /// Read the current value of the clock.
    ///
    /// The clock is monotonic, therefore calling this function repeatedly will
    /// produce a sequence of non-decreasing values.
    now: func() -> instant;

    /// Query the resolution of the clock. Returns the duration of time
    /// corresponding to a clock tick.
    resolution: func() -> duration;

    /// Create a `pollable` which will resolve once the specified instant
    /// occured.
    subscribe-instant: func(
        when: instant,
    ) -> pollable;

    /// Create a `pollable` which will resolve once the given duration has
    /// elapsed, starting at the time at which this function was called.
    /// occured.
    subscribe-duration: func(
        when: duration,
    ) -> pollable;
}