| // Copyright 2022 The Tint Authors. |
| // |
| // 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 SRC_TINT_UTILS_TEXT_UNICODE_H_ |
| #define SRC_TINT_UTILS_TEXT_UNICODE_H_ |
| |
| #include <cstddef> |
| #include <cstdint> |
| #include <string_view> |
| #include <utility> |
| |
| namespace tint { |
| |
| /// CodePoint is a unicode code point. |
| struct CodePoint { |
| /// Constructor |
| inline CodePoint() = default; |
| |
| /// Constructor |
| /// @param v the code point value |
| inline explicit CodePoint(uint32_t v) : value(v) {} |
| |
| /// @returns the code point value |
| inline operator uint32_t() const { return value; } |
| |
| /// Assignment operator |
| /// @param v the new value for the code point |
| /// @returns this CodePoint |
| inline CodePoint& operator=(uint32_t v) { |
| value = v; |
| return *this; |
| } |
| |
| /// @returns true if this CodePoint is in the XID_Start set. |
| /// @see https://unicode.org/reports/tr31/ |
| bool IsXIDStart() const; |
| |
| /// @returns true if this CodePoint is in the XID_Continue set. |
| /// @see https://unicode.org/reports/tr31/ |
| bool IsXIDContinue() const; |
| |
| /// The code point value |
| uint32_t value = 0; |
| }; |
| |
| namespace utf8 { |
| |
| /// Decodes the first code point in the utf8 string. |
| /// @param ptr the pointer to the first byte of the utf8 sequence |
| /// @param len the maximum number of bytes to read |
| /// @returns a pair of CodePoint and width in code units (bytes). |
| /// If the next code point cannot be decoded then returns [0,0]. |
| std::pair<CodePoint, size_t> Decode(const uint8_t* ptr, size_t len); |
| |
| /// Decodes the first code point in the utf8 string. |
| /// @param utf8_string the string view that contains the utf8 sequence |
| /// @returns a pair of CodePoint and width in code units (bytes). |
| /// If the next code point cannot be decoded then returns [0,0]. |
| std::pair<CodePoint, size_t> Decode(std::string_view utf8_string); |
| |
| /// @returns true if all the utf-8 code points in the string are ASCII |
| /// (code-points 0x00..0x7f). |
| bool IsASCII(std::string_view); |
| |
| } // namespace utf8 |
| |
| } // namespace tint |
| |
| #endif // SRC_TINT_UTILS_TEXT_UNICODE_H_ |