Added `DurationProvider`, `ThrottleProvider` traits.

Fortune for throttle's current commit: Half blessing − 半吉

.gitignore

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+/target

Cargo.lock

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Cargo.toml

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+[package]
+name = "throttle"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rand = "0.8.5"

src/main.rs

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+
+mod prov;
+mod stream;
+
+fn main() {
+    println!("Hello, world!");
+}

src/prov.rs

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+//! Throttle provider
+use std::time::Duration;
+use std::iter;
+
+pub trait DurationProvider
+{
+    fn get_next_duration(&mut self) -> Option<Duration>;
+}
+
+/// An iterator adaptor for a `DurationProvider`.
+#[derive(Debug, Clone)]
+pub struct DurationProviderIter<T: ?Sized>(T);
+
+impl<T> DurationProviderIter<T>
+{
+    /// Consume into the backing `DurationProvider`
+    #[inline(always)] 
+    pub fn into_inner(self) -> T
+    {
+	self.0
+    }
+}
+
+impl<T: ?Sized + DurationProvider> Iterator for DurationProviderIter<T>
+{
+    type Item = Duration;
+    #[inline(always)] 
+    fn next(&mut self) -> Option<Self::Item>
+    {
+	self.0.get_next_duration()
+    }
+}
+
+
+pub trait DurationProviderIterExt<'a>
+{
+    type Iter: iter::Iterator<Item=Duration> + 'a;
+    fn get_all_durations(self) -> Self::Iter;
+}
+
+pub trait DurationProviderExt<'a>
+{
+    fn get_all_durations_dyn(self: Box<Self>) -> Box<dyn iter::Iterator<Item=Duration> + 'a>;
+}
+
+impl<'a, T: DurationProvider + 'a> DurationProviderIterExt<'a> for T
+{
+    type Iter = DurationProviderIter<Self>;
+    #[inline(always)] 
+    fn get_all_durations(self) -> Self::Iter {
+	DurationProviderIter(self)
+    }
+}
+
+impl<'a, T: ?Sized + DurationProvider + 'a> DurationProviderExt<'a> for T
+{
+    #[inline] 
+    fn get_all_durations_dyn(self: Box<Self>) -> Box<dyn iter::Iterator<Item=Duration> + 'a>
+    {
+	#[derive(Debug)]
+	struct Iter<T: ?Sized>(Box<T>);
+	impl<T: DurationProvider+?Sized> Iterator for Iter<T>
+	{
+	    type Item = Duration;
+	    fn next(&mut self) -> Option<Self::Item>
+	    {
+		self.0.get_next_duration()
+	    }
+	}
+
+	Box::new(Iter(self))
+    }
+}
+
+impl DurationProvider for Duration
+{
+    #[inline(always)] 
+    fn get_next_duration(&mut self) -> Option<Duration> {
+	Some(*self)
+    }
+}
+
+pub trait ThrottleProvider
+{
+    type Timer: DurationProvider;
+    fn get_timeout(&self) -> Self::Timer;
+}
+
+
+pub trait DynThrottleProvider
+{
+    fn get_timeout(&self) -> Box<dyn DurationProvider + '_>;
+}
+impl<T: ?Sized> DynThrottleProvider for T
+where T: ThrottleProvider
+{
+    #[inline(always)] 
+    fn get_timeout(&self) -> Box<dyn DurationProvider + '_>
+    {
+	Box::new(ThrottleProvider::get_timeout(&self))
+    }
+}
+
+impl<'a, T: ?Sized> ThrottleProvider for &'a T
+where T: ThrottleProvider
+{
+    type Timer = T::Timer;
+    #[inline(always)] 
+    fn get_timeout(&self) -> Self::Timer {
+	T::get_timeout(self)
+    }
+}
+
+impl ThrottleProvider for Duration
+{
+    type Timer = Self;
+    fn get_timeout(&self) -> Self::Timer {
+	self.clone()
+    }
+}
+
+/// Provides a throttle adaptor that returns a uniformly-distributed `T` each time `get_timeout()` is called. 
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct UniformThrottleProvider<T: ?Sized, R: std::ops::RangeBounds<T>>(R, std::marker::PhantomData<T>);
+
+impl<T: ?Sized, R> From<R> for UniformThrottleProvider<T, R>
+where T: DurationProvider,
+      R: std::ops::RangeBounds<T>
+{
+    #[inline(always)] 
+    fn from(from: R) -> Self
+    {
+	Self(from, std::marker::PhantomData)
+    }
+}
+
+impl<T, R> ThrottleProvider for UniformThrottleProvider<T, R>
+where T: DurationProvider + rand::distributions::uniform::SampleUniform,
+      R: std::ops::RangeBounds<T>,
+for <'r> &'r R: rand::distributions::uniform::SampleRange<T>,
+{
+    type Timer = T;
+    #[inline] 
+    fn get_timeout(&self) -> Self::Timer {
+	use rand::prelude::*;
+	rand::thread_rng().gen_range(&self.0)
+    }
+}

src/stream.rs

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+//! Stream adaptors
+use super::*;
+
+
+pub struct ThrottleAdaptor<R, T>
+{
+    reader: R,
+    timeout_provider: T
+}