lexers/javascript.lua

   1 -- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- JavaScript LPeg lexer.
   3
   4 local l = require('lexer')
   5 local token, word_match = l.token, l.word_match
   6 local P, R, S = lpeg.P, lpeg.R, lpeg.S
   7
   8 local M = {_NAME = 'javascript'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local line_comment = '//' * l.nonnewline_esc^0
  15 local block_comment = '/*' * (l.any - '*/')^0 * P('*/')^-1
  16 local comment = token(l.COMMENT, line_comment + block_comment)
  17
  18 -- Strings.
  19 local sq_str = l.delimited_range("'")
  20 local dq_str = l.delimited_range('"')
  21 local regex_str = #P('/') * l.last_char_includes('+-*%^!=&|?:;,([{<>') *
  22                   l.delimited_range('/', true) * S('igm')^0
  23 local string = token(l.STRING, sq_str + dq_str) + token(l.REGEX, regex_str)
  24
  25 -- Numbers.
  26 local number = token(l.NUMBER, l.float + l.integer)
  27
  28 -- Keywords.
  29 local keyword = token(l.KEYWORD, word_match{
  30   'abstract', 'boolean', 'break', 'byte', 'case', 'catch', 'char', 'class',
  31   'const', 'continue', 'debugger', 'default', 'delete', 'do', 'double', 'else',
  32   'enum', 'export', 'extends', 'false', 'final', 'finally', 'float', 'for',
  33   'function', 'goto', 'if', 'implements', 'import', 'in', 'instanceof', 'int',
  34   'interface', 'let', 'long', 'native', 'new', 'null', 'package', 'private',
  35   'protected', 'public', 'return', 'short', 'static', 'super', 'switch',
  36   'synchronized', 'this', 'throw', 'throws', 'transient', 'true', 'try',
  37   'typeof', 'var', 'void', 'volatile', 'while', 'with', 'yield'
  38 })
  39
  40 -- Identifiers.
  41 local identifier = token(l.IDENTIFIER, l.word)
  42
  43 -- Operators.
  44 local operator = token(l.OPERATOR, S('+-/*%^!=&|?:;,.()[]{}<>'))
  45
  46 M._rules = {
  47   {'whitespace', ws},
  48   {'keyword', keyword},
  49   {'identifier', identifier},
  50   {'comment', comment},
  51   {'number', number},
  52   {'string', string},
  53   {'operator', operator},
  54 }
  55
  56 M._foldsymbols = {
  57   _patterns = {'[{}]', '/%*', '%*/', '//'},
  58   [l.OPERATOR] = {['{'] = 1, ['}'] = -1},
  59   [l.COMMENT] = {['/*'] = 1, ['*/'] = -1, ['//'] = l.fold_line_comments('//')}
  60 }
  61
  62 return M