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// Copyright 2015 The Cobalt Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef COBALT_CSSOM_CHARACTER_CLASSIFICATION_H_
#define COBALT_CSSOM_CHARACTER_CLASSIFICATION_H_
namespace cobalt {
namespace cssom {
// Checks whether a character is affected by a CSS white space processing.
// https://www.w3.org/TR/css3-text/#white-space-rules
inline bool IsWhiteSpace(char character) {
// Histogram from Apple's page load test combined with some ad hoc browsing
// some other test suites.
//
// 82%: 216330 non-space characters, all > U+0020
// 11%: 30017 plain space characters, U+0020
// 5%: 12099 newline characters, U+000A
// 2%: 5346 tab characters, U+0009
//
// No other characters seen. No U+000C or U+000D, and no other control
// characters. Accordingly, we check for non-spaces first, then space,
// then newline, then tab, then the other characters.
return character <= ' ' &&
(character == ' ' || character == '\n' || character == '\t' ||
character == '\r' || character == '\f');
}
} // namespace cssom
} // namespace cobalt
#endif // COBALT_CSSOM_CHARACTER_CLASSIFICATION_H_