/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").  
 * You may not use this file except in compliance with the License.
 *
 * See LICENSE.txt included in this distribution for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at LICENSE.txt.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
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/*
 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2017, Chris Fraire <cfraire@me.com>.
 *
 * Copyright (c) Simon Peyton Jones. 
 * Copyright (c) Simon Marlow.
 * The authors and publisher intend this Report to belong to the entire Haskell
 * community, and grant permission to copy and distribute it for any purpose,
 * provided that it is reproduced in its entirety, including this Notice.
 * Modified versions of this Report may also be copied and distributed for any
 * purpose, provided that the modified version is clearly presented as such,
 * and that it does not claim to be a definition of the language Haskell 2010.
 */

Identifier = ({varid} | {conid})
/*
 * varid	→	(small {small | large | digit | ' })⟨reservedid⟩
 * ; N.b. "except {reservedid} is excluded from OpenGrok's varid definition
 */
varid = {small} ({small} | {large} | {digit} | [\'])*
/*
 * conid	→	large {small | large | digit | ' }
 */
conid = {large} ({small} | {large} | {digit} | [\'])*
/*
 * small	→	ascSmall | uniSmall | _
 * ascSmall	→	a | b | … | z
 * uniSmall	→	any Unicode lowercase letter
 */
small = [a-z\p{Ll}_]
/*
 * large	→	ascLarge | uniLarge
 * ascLarge	→	A | B | … | Z
 * uniLarge	→	any uppercase or titlecase Unicode letter
 */
large = [A-Z\p{Lu}\p{Lt}]
/*
 * digit	→	ascDigit | uniDigit
 * ascDigit	→	0 | 1 | … | 9
 * uniDigit	→	any Unicode decimal digit
 * octit	→	0 | 1 | … | 7
 * hexit	→	digit | A | … | F | a | … | f
 */
digit = [0-9\p{Nd}]
octit = [0-7]
hexit = [0-9\p{Nd}A-Fa-f]

Number = ({integer} | {float})
/*
 * decimal	→	digit{digit}
 * octal	→	octit{octit}
 * hexadecimal	→	hexit{hexit}
 */
decimal         = {digit}+
octal           = {octit}+
hexadecimal     = {hexit}+
/*
 *
 * integer	→	decimal
 *		|	0o octal | 0O octal
 *		|	0x hexadecimal | 0X hexadecimal
 */
integer = ({decimal} | [0][oO]{octal} | [0][xX]{hexadecimal})
/*
 * float	→	decimal . decimal [exponent]
 *		|	decimal exponent
 */
float = ({decimal} [\.] {decimal} {exponent}? |
    {decimal} {exponent})
/*
 * exponent	→	(e | E) [+ | -] decimal
 */
exponent = [eE] [\+\-]? {decimal}

/*
 * "For example, '-->' or '|--' do not begin a comment, because both of these
 * are legal lexemes;"
 */
NotComments = ("-->" | "|--")