text: // Copyright (C) 2013 Andrew Allen
  //
  // 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.
  
  
  /**
   * @fileoverview
   * Registers a language handler for Erlang.
   *
   * Derived from https://raw.github.com/erlang/otp/dev/Libs/compiler/src/core_parse.yrl
   * Modified from Mike Samuel's Haskell plugin for google-code-prettify
   *
   * @author achew22@gmail.com
   */
  
  PR['registerLangHandler'](
      PR['createSimpleLexer'](
          [
           // Whitespace
           // whitechar    ->    newline | vertab | space | tab | uniWhite
           // newline      ->    return linefeed | return | linefeed | formfeed
           [PR['PR_PLAIN'],       /^[\t\n\x0B\x0C\r ]+/, null, '\t\n\x0B\x0C\r '],
           // Single line double-quoted strings.
           [PR['PR_STRING'],      /^\"(?:[^\"\\\n\x0C\r]|\\[\s\S])*(?:\"|$)/,
            null, '"'],
           
           // Handle atoms
           [PR['PR_LITERAL'],      /^[a-z][a-zA-Z0-9_]*/],
           // Handle single quoted atoms
           [PR['PR_LITERAL'],      /^\'(?:[^\'\\\n\x0C\r]|\\[^&])+\'?/,
            null, "'"],
           
           // Handle macros. Just to be extra clear on this one, it detects the ?
           // then uses the regexp to end it so be very careful about matching
           // all the terminal elements
           [PR['PR_LITERAL'],      /^\?[^ \t\n({]+/, null, "?"],
  
            
           
           // decimal      ->    digit{digit}
           // octal        ->    octit{octit}
           // hexadecimal  ->    hexit{hexit}
           // integer      ->    decimal
           //               |    0o octal | 0O octal
           //               |    0x hexadecimal | 0X hexadecimal
           // float        ->    decimal . decimal [exponent]
           //               |    decimal exponent
           // exponent     ->    (e | E) [+ | -] decimal
           [PR['PR_LITERAL'],
            /^(?:0o[0-7]+|0x[\da-f]+|\d+(?:\.\d+)?(?:e[+\-]?\d+)?)/i,
            null, '0123456789']
          ],
          [
           // TODO: catch @declarations inside comments
  
           // Comments in erlang are started with % and go till a newline
           [PR['PR_COMMENT'], /^%[^\n]*/],
  
           // Catch macros
           //[PR['PR_TAG'], /?[^( \n)]+/],
  
           /**
            * %% Keywords (atoms are assumed to always be single-quoted).
            * 'module' 'attributes' 'do' 'let' 'in' 'letrec'
            * 'apply' 'call' 'primop'
            * 'case' 'of' 'end' 'when' 'fun' 'try' 'catch' 'receive' 'after'
            */
           [PR['PR_KEYWORD'], /^(?:module|attributes|do|let|in|letrec|apply|call|primop|case|of|end|when|fun|try|catch|receive|after|char|integer|float,atom,string,var)\b/],
           
           /**
            * Catch definitions (usually defined at the top of the file)
            * Anything that starts -something
            */
           [PR['PR_KEYWORD'], /^-[a-z_]+/],
  
           // Catch variables
           [PR['PR_TYPE'], /^[A-Z_][a-zA-Z0-9_]*/],
  
           // matches the symbol production
           [PR['PR_PUNCTUATION'], /^[.,;]/]
          ]),
      ['erlang', 'erl']);
  