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#![warn(clippy::pedantic)]
#![doc(html_root_url = "https://docs.rs/gnaw/0.0.2")]
#[cfg(doctest)]
pub mod readme {
doc_comment::doctest!("../README.md");
}
mod drains;
use drains::{SliceDrain, StrDrain};
pub trait Drain<'a, T> {
type Target: DoubleEndedIterator<Item = T> + 'a;
fn drain(&'a mut self) -> Self::Target;
}
pub trait Pop<T> {
fn pop(&mut self) -> Option<T>;
}
pub trait Unshift<T> {
fn unshift(&mut self) -> Option<T>;
}
impl<'a, T: 'a> Drain<'a, &'a T> for &'a [T] {
type Target = SliceDrain<'a, T>;
fn drain(&'a mut self) -> Self::Target {
SliceDrain(self)
}
}
impl<'a> Drain<'a, char> for &'a str {
type Target = StrDrain<'a>;
fn drain(&'a mut self) -> Self::Target {
StrDrain(self)
}
}
impl<'a, T> Pop<&'a T> for &'a [T] {
fn pop(&mut self) -> Option<&'a T> {
self.split_last().map(|(t, rest)| {
*self = rest;
t
})
}
}
impl Pop<char> for &str {
fn pop(&mut self) -> Option<char> {
let c = self.chars().last();
if let Some(c) = c {
*self = &self[..self.len() - c.len_utf8()];
}
c
}
}
impl<'a, T> Unshift<&'a T> for &'a [T] {
fn unshift(&mut self) -> Option<&'a T> {
self.split_first().map(|(t, rest)| {
*self = rest;
t
})
}
}
impl Unshift<char> for &str {
fn unshift(&mut self) -> Option<char> {
let c = self.chars().next();
if let Some(c) = c {
*self = &self[c.len_utf8()..];
}
c
}
}