lexers/coffeescript.lua

   1 -- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- CoffeeScript LPeg lexer.
   3
   4 local l = require('lexer')
   5 local token, word_match = l.token, l.word_match
   6 local P, S = lpeg.P, lpeg.S
   7
   8 local M = {_NAME = 'coffeescript'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local block_comment = '###' * (l.any - '###')^0 * P('###')^-1
  15 local line_comment = '#' * l.nonnewline_esc^0
  16 local comment = token(l.COMMENT, block_comment + line_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   'all', 'and', 'bind', 'break', 'by', 'case', 'catch', 'class', 'const',
  31   'continue', 'default', 'delete', 'do', 'each', 'else', 'enum', 'export',
  32   'extends', 'false', 'for', 'finally', 'function', 'if', 'import', 'in',
  33   'instanceof', 'is', 'isnt', 'let', 'loop', 'native', 'new', 'no', 'not', 'of',
  34   'off', 'on', 'or', 'return', 'super', 'switch', 'then', 'this', 'throw',
  35   'true', 'try', 'typeof', 'unless', 'until', 'var', 'void', 'with', 'when',
  36   'while', 'yes'
  37 })
  38
  39 -- Fields: object properties and methods.
  40 local field = token(l.FUNCTION, '.' * (S('_$') + l.alpha) *
  41                                 (S('_$') + l.alnum)^0)
  42
  43 -- Identifiers.
  44 local identifier = token(l.IDENTIFIER, l.word)
  45
  46 -- Operators.
  47 local operator = token(l.OPERATOR, S('+-/*%<>!=^&|?~:;,.()[]{}'))
  48
  49 M._rules = {
  50   {'whitespace', ws},
  51   {'keyword', keyword},
  52   {'field', field},
  53   {'identifier', identifier},
  54   {'comment', comment},
  55   {'number', number},
  56   {'string', string},
  57   {'operator', operator},
  58 }
  59
  60 M._FOLDBYINDENTATION = true
  61
  62 return M