mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-20 00:35:44 +00:00
121224a608
Source-Repo: https://github.com/servo/servo Source-Revision: 87847324a0815e2214fd34da89bbefa4222b1197
54 lines
1.4 KiB
Rust
54 lines
1.4 KiB
Rust
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
//! Small helpers to abstract over different containers.
|
|
#![deny(missing_docs)]
|
|
|
|
use smallvec::{Array, SmallVec};
|
|
use std::marker::PhantomData;
|
|
|
|
/// A trait to abstract over a `push` method that may be implemented for
|
|
/// different kind of types.
|
|
///
|
|
/// Used to abstract over `Array`, `SmallVec` and `Vec`, and also to implement a
|
|
/// type which `push` method does only tweak a byte when we only need to check
|
|
/// for the presence of something.
|
|
pub trait Push<T> {
|
|
/// Push a value into self.
|
|
fn push(&mut self, value: T);
|
|
}
|
|
|
|
impl<T> Push<T> for Vec<T> {
|
|
fn push(&mut self, value: T) {
|
|
Vec::push(self, value);
|
|
}
|
|
}
|
|
|
|
impl<A: Array> Push<A::Item> for SmallVec<A> {
|
|
fn push(&mut self, value: A::Item) {
|
|
SmallVec::push(self, value);
|
|
}
|
|
}
|
|
|
|
/// A struct that implements `Push`, but only stores whether it's empty.
|
|
pub struct ForgetfulSink<T>(bool, PhantomData<T>);
|
|
|
|
impl<T> ForgetfulSink<T> {
|
|
/// Trivially construct a new `ForgetfulSink`.
|
|
pub fn new() -> Self {
|
|
ForgetfulSink(true, PhantomData)
|
|
}
|
|
|
|
/// Whether this sink is empty or not.
|
|
pub fn is_empty(&self) -> bool {
|
|
self.0
|
|
}
|
|
}
|
|
|
|
impl<T> Push<T> for ForgetfulSink<T> {
|
|
fn push(&mut self, _value: T) {
|
|
self.0 = false;
|
|
}
|
|
}
|