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/* 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 https://mozilla.org/MPL/2.0/. */
//! A type to represent a namespace.
use crate::gecko_bindings::structs::nsAtom;
use crate::string_cache::{Atom, WeakAtom};
use precomputed_hash::PrecomputedHash;
use std::borrow::Borrow;
use std::fmt;
use std::ops::Deref;
/// In Gecko namespaces are just regular atoms, so this is a simple macro to
/// forward one macro to the other.
#[macro_export]
macro_rules! ns {
() => {
$crate::string_cache::Namespace(atom!(""))
};
($s:tt) => {
$crate::string_cache::Namespace(atom!($s))
};
}
/// A Gecko namespace is just a wrapped atom.
#[derive(
Clone,
Debug,
Default,
Eq,
Hash,
MallocSizeOf,
PartialEq,
ToComputedValue,
ToResolvedValue,
ToShmem,
)]
#[repr(transparent)]
pub struct Namespace(pub Atom);
impl PrecomputedHash for Namespace {
#[inline]
fn precomputed_hash(&self) -> u32 {
self.0.precomputed_hash()
}
}
/// A Gecko WeakNamespace is a wrapped WeakAtom.
#[derive(Deref, Hash)]
pub struct WeakNamespace(WeakAtom);
impl Deref for Namespace {
type Target = WeakNamespace;
#[inline]
fn deref(&self) -> &WeakNamespace {
let weak: *const WeakAtom = &*self.0;
unsafe { &*(weak as *const WeakNamespace) }
}
}
impl<'a> From<&'a str> for Namespace {
fn from(s: &'a str) -> Self {
Namespace(Atom::from(s))
}
}
impl fmt::Display for Namespace {
fn fmt(&self, w: &mut fmt::Formatter) -> fmt::Result {
self.0.fmt(w)
}
}
impl Borrow<WeakNamespace> for Namespace {
#[inline]
fn borrow(&self) -> &WeakNamespace {
self
}
}
impl WeakNamespace {
/// Trivially construct a WeakNamespace.
#[inline]
pub unsafe fn new<'a>(atom: *mut nsAtom) -> &'a Self {
&*(atom as *const WeakNamespace)
}
/// Clone this WeakNamespace to obtain a strong reference to the same
/// underlying namespace.
#[inline]
pub fn clone(&self) -> Namespace {
Namespace(self.0.clone())
}
}
impl Eq for WeakNamespace {}
impl PartialEq for WeakNamespace {
#[inline]
fn eq(&self, other: &Self) -> bool {
let weak: *const WeakNamespace = self;
let other: *const WeakNamespace = other;
weak == other
}
}