1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * See LICENSE.txt included in this distribution for the specific 9 * language governing permissions and limitations under the License. 10 * 11 * When distributing Covered Code, include this CDDL HEADER in each 12 * file and include the License file at LICENSE.txt. 13 * If applicable, add the following below this CDDL HEADER, with the 14 * fields enclosed by brackets "[]" replaced with your own identifying 15 * information: Portions Copyright [yyyy] [name of copyright owner] 16 * 17 * CDDL HEADER END 18 */ 19 20/* 21 * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved. 22 * Portions Copyright (c) 2017-2018, Chris Fraire <cfraire@me.com>. 23 * 24 * Copyright (c) 2018 cppreference.com 25 * http://en.cppreference.com/w/Cppreference:FAQ 26 * "You can use this site in almost any way you like, including mirroring, 27 * copying, translating, etc. All we would ask is to provide link back to 28 * cppreference.com so that people know where to get the most up-to-date 29 * content." 30 */ 31 32Identifier = [a-zA-Z_] [a-zA-Z0-9_]* 33 34/* 35 * An integer constant is a non-lvalue expression of the form 36 * 37 * decimal-constant integer-suffix(optional) (1) 38 * octal-constant integer-suffix(optional) (2) 39 * hex-constant integer-suffix(optional) (3) 40 * where 41 * 42 * decimal-constant is a non-zero decimal digit (1, 2, 3, 4, 5, 6, 7, 8, 9), 43 * followed by zero or more decimal digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) 44 * 45 * octal-constant is the digit zero (0) followed by zero or more octal digits 46 * (0, 1, 2, 3, 4, 5, 6, 7) 47 * 48 * hex-constant is the character sequence 0x or the character sequence 0X 49 * followed by one or more hexadecimal digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, 50 * A, b, B, c, C, d, D, e, E, f, F) 51 * 52 * integer-suffix, if provided, may contain one or both of the following (if 53 * both are provided, they may appear in any order: 54 * 55 * unsigned-suffix (the character u or the character U) 56 * 57 * long-suffix (the character l or the character L) or the long-long-suffix 58 * (the character sequence ll or the character sequence LL) (since C99) 59 */ 60integer_literal = ({decimal_literal} | {octal_literal} | {hex_literal}) 61decimal_literal = [1-9] [0-9]* {integer_suffix}? 62octal_literal = 0[0-7]+ {integer_suffix}? 63hex_literal = 0[xX][0-9a-fA-F]+ {integer_suffix}? 64 65integer_suffix = ({unsigned_suffix} | {long_suffix})+ 66unsigned_suffix = [uU] 67long_suffix = ([lL] | "ll" | "LL") 68 69/* 70 * A floating constant is a non-lvalue expression having the form: 71 * 72 * significand exponent(optional) suffix(optional) 73 * Where the significand has the form 74 * 75 * whole-number(optional) .(optional) fraction(optional) 76 * The exponent has the form 77 * 78 * e | E exponent-sign(optional) digit-sequence (1) 79 * p | P exponent-sign(optional) digit-sequence (2) (since C99) 80 * 1) The exponent syntax for a decimal floating-point constant 81 * 2) The exponent syntax for hexadecimal floating-point constant 82 * 83 * (The C++ standard had better break-down of "significand" so the following 84 * is taken from it, without support for apostrophe delimiters.) 85 */ 86fp_literal = ({fp1} | {fp2} | {fp3} | {fp4} | {fp5} | {fp6}) {fp_suffix}? 87fp1 = {digit_seq} {fp_exp} 88fp2 = {digit_seq} \. {fp_exp}? 89fp3 = (\. {digit_seq} | {digit_seq} \. {digit_seq}) {fp_exp}? 90fp4 = 0[xX] {hex_digit_seq} {fp_exp} 91fp5 = 0[xX] {hex_digit_seq} \. {fp_exp}? 92fp6 = 0[xX] (\. {hex_digit_seq} | {hex_digit_seq} \. {hex_digit_seq}) {fp_exp}? 93 94digit_seq = [0-9]+ 95hex_digit_seq = [0-9a-fA-F]+ 96fp_exp = [eEpP][\+\-]?{digit_seq} 97fp_suffix = [fFlLdD] // [dD] is only present for OpenGrok compatibility 98 99Number = [\+\-]? ({integer_literal} | {fp_literal}) 100