//===- llvm/Support/Unicode.h - Unicode character properties -*- C++ -*-=====// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file defines functions that allow querying certain properties of Unicode // characters. // //===----------------------------------------------------------------------===// #ifndef LLVM_SUPPORT_UNICODE_H #define LLVM_SUPPORT_UNICODE_H namespace llvm { class StringRef; namespace sys { namespace unicode { enum ColumnWidthErrors { ErrorInvalidUTF8 = -2, ErrorNonPrintableCharacter = -1 }; /// Determines if a character is likely to be displayed correctly on the /// terminal. Exact implementation would have to depend on the specific /// terminal, so we define the semantic that should be suitable for generic case /// of a terminal capable to output Unicode characters. /// /// All characters from the Unicode code point range are considered printable /// except for: /// * C0 and C1 control character ranges; /// * default ignorable code points as per 5.21 of /// http://www.unicode.org/versions/Unicode6.2.0/UnicodeStandard-6.2.pdf /// except for U+00AD SOFT HYPHEN, as it's actually displayed on most /// terminals; /// * format characters (category = Cf); /// * surrogates (category = Cs); /// * unassigned characters (category = Cn). /// \return true if the character is considered printable. bool isPrintable(int UCS); /// Gets the number of positions the UTF8-encoded \p Text is likely to occupy /// when output on a terminal ("character width"). This depends on the /// implementation of the terminal, and there's no standard definition of /// character width. /// /// The implementation defines it in a way that is expected to be compatible /// with a generic Unicode-capable terminal. /// /// \return Character width: /// * ErrorNonPrintableCharacter (-1) if \p Text contains non-printable /// characters (as identified by isPrintable); /// * 0 for each non-spacing and enclosing combining mark; /// * 2 for each CJK character excluding halfwidth forms; /// * 1 for each of the remaining characters. int columnWidthUTF8(StringRef Text); /// Fold input unicode character according the Simple unicode case folding /// rules. int foldCharSimple(int C); } // namespace unicode } // namespace sys } // namespace llvm #endif