42 lines
1016 B
C++
42 lines
1016 B
C++
/*
|
|
* Copyright (c) Meta Platforms, Inc. and affiliates.
|
|
*
|
|
* This source code is licensed under the MIT license found in the
|
|
* LICENSE file in the root directory of this source tree.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <optional>
|
|
|
|
#include <react/renderer/css/CSSDataType.h>
|
|
|
|
namespace facebook::react {
|
|
|
|
/**
|
|
* The value <zero> represents a literal number with the value 0. Expressions
|
|
* that merely evaluate to a <number> with the value 0 (for example, calc(0)) do
|
|
* not match <zero>; only literal <number-token>s do.
|
|
*
|
|
* https://www.w3.org/TR/css-values-4/#zero-value
|
|
*/
|
|
struct CSSZero {
|
|
constexpr bool operator==(const CSSZero &rhs) const = default;
|
|
};
|
|
|
|
template <>
|
|
struct CSSDataTypeParser<CSSZero> {
|
|
static constexpr auto consumePreservedToken(const CSSPreservedToken &token) -> std::optional<CSSZero>
|
|
{
|
|
if (token.type() == CSSTokenType::Number && token.numericValue() == 0) {
|
|
return CSSZero{};
|
|
}
|
|
|
|
return {};
|
|
}
|
|
};
|
|
|
|
static_assert(CSSDataType<CSSZero>);
|
|
|
|
} // namespace facebook::react
|