/**
 * @fileoverview
 * Registers a language handler for VHDL '93.
 *
 * Based on the lexical grammar and keywords at
 * http://www.iis.ee.ethz.ch/~zimmi/download/vhdl93_syntax.html
 *
 * @author benoit@ryder.fr
 */

PR.registerLangHandler(
    PR.createSimpleLexer(
        [
         // Whitespace
         [PR.PR_PLAIN, /^[\t\n\r \xA0]+/, null, '\t\n\r \xA0']
        ],
        [
         // String, character or bit string
         [PR.PR_STRING, /^(?:[BOX]?"(?:[^\"]|"")*"|'.')/i],
         // Comment, from two dashes until end of line.
         [PR.PR_COMMENT, /^--[^\r\n]*/],
         [PR.PR_KEYWORD, /^(?:abs|access|after|alias|all|and|architecture|array|assert|attribute|begin|block|body|buffer|bus|case|component|configuration|constant|disconnect|downto|else|elsif|end|entity|exit|file|for|function|generate|generic|group|guarded|if|impure|in|inertial|inout|is|label|library|linkage|literal|loop|map|mod|nand|new|next|nor|not|null|of|on|open|or|others|out|package|port|postponed|procedure|process|pure|range|record|register|reject|rem|report|return|rol|ror|select|severity|shared|signal|sla|sll|sra|srl|subtype|then|to|transport|type|unaffected|units|until|use|variable|wait|when|while|with|xnor|xor)(?=[^\w-]|$)/i, null],
         // Type, predefined or standard
         [PR.PR_TYPE, /^(?:bit|bit_vector|character|boolean|integer|real|time|string|severity_level|positive|natural|signed|unsigned|line|text|std_u?logic(?:_vector)?)(?=[^\w-]|$)/i, null],
         // Predefined attributes
         [PR.PR_TYPE, /^\'(?:ACTIVE|ASCENDING|BASE|DELAYED|DRIVING|DRIVING_VALUE|EVENT|HIGH|IMAGE|INSTANCE_NAME|LAST_ACTIVE|LAST_EVENT|LAST_VALUE|LEFT|LEFTOF|LENGTH|LOW|PATH_NAME|POS|PRED|QUIET|RANGE|REVERSE_RANGE|RIGHT|RIGHTOF|SIMPLE_NAME|STABLE|SUCC|TRANSACTION|VAL|VALUE)(?=[^\w-]|$)/i, null],
         // Number, decimal or based literal
         [PR.PR_LITERAL, /^\d+(?:_\d+)*(?:#[\w\\.]+#(?:[+\-]?\d+(?:_\d+)*)?|(?:\.\d+(?:_\d+)*)?(?:E[+\-]?\d+(?:_\d+)*)?)/i],
         // Identifier, basic or extended
         [PR.PR_PLAIN, /^(?:[a-z]\w*|\\[^\\]*\\)/i],
         // Punctuation
         [PR.PR_PUNCTUATION, /^[^\w\t\n\r \xA0\"\'][^\w\t\n\r \xA0\-\"\']*/]
        ]),
    ['vhdl', 'vhd']);