gecko-dev/servo/components/style/macros.rs
Emilio Cobos Álvarez 5c0f63af95 Bug 1851649 - Simplify and speed-up display parsing. r=mstange
This avoids uselessly rewinding the parser for single-keyword display
values, and generally makes the code easier to follow.

Differential Revision: https://phabricator.services.mozilla.com/D187431
2023-09-05 17:44:09 +00:00

99 lines
2.6 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 https://mozilla.org/MPL/2.0/. */
//! Various macro helpers.
macro_rules! exclusive_value {
(($value:ident, $set:expr) => $ident:path) => {
if $value.intersects($set) {
return Err(());
} else {
$ident
}
};
}
#[cfg(feature = "gecko")]
macro_rules! impl_gecko_keyword_conversions {
($name:ident, $utype:ty) => {
impl From<$utype> for $name {
fn from(bits: $utype) -> $name {
$name::from_gecko_keyword(bits)
}
}
impl From<$name> for $utype {
fn from(v: $name) -> $utype {
v.to_gecko_keyword()
}
}
};
}
macro_rules! trivial_to_computed_value {
($name:ty) => {
impl $crate::values::computed::ToComputedValue for $name {
type ComputedValue = $name;
fn to_computed_value(&self, _: &$crate::values::computed::Context) -> Self {
self.clone()
}
fn from_computed_value(other: &Self) -> Self {
other.clone()
}
}
};
}
/// A macro to parse an identifier, or return an `UnexpectedIdent` error
/// otherwise.
///
/// FIXME(emilio): The fact that `UnexpectedIdent` is a `SelectorParseError`
/// doesn't make a lot of sense to me.
macro_rules! try_match_ident_ignore_ascii_case {
($input:expr, $( $match_body:tt )*) => {{
let location = $input.current_source_location();
let ident = $input.expect_ident()?;
match_ignore_ascii_case! { &ident,
$( $match_body )*
_ => return Err(location.new_custom_error(
::selectors::parser::SelectorParseErrorKind::UnexpectedIdent(ident.clone())
))
}
}}
}
#[cfg(feature = "servo")]
macro_rules! local_name {
($s:tt) => {
$crate::values::GenericAtomIdent(html5ever::local_name!($s))
};
}
#[cfg(feature = "servo")]
macro_rules! ns {
() => {
$crate::values::GenericAtomIdent(html5ever::ns!())
};
($s:tt) => {
$crate::values::GenericAtomIdent(html5ever::ns!($s))
};
}
#[cfg(feature = "gecko")]
macro_rules! local_name {
($s:tt) => {
$crate::values::AtomIdent(atom!($s))
};
}
/// Asserts the size of a type at compile time.
macro_rules! size_of_test {
($t: ty, $expected_size: expr) => {
#[cfg(target_pointer_width = "64")]
const_assert_eq!(std::mem::size_of::<$t>(), $expected_size);
};
}