lexers/ini.lua

   1 -- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- Ini 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 = 'ini'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local comment = token(l.COMMENT, l.starts_line(S(';#')) * l.nonnewline^0)
  15
  16 -- Strings.
  17 local sq_str = l.delimited_range("'")
  18 local dq_str = l.delimited_range('"')
  19 local label = l.delimited_range('[]', true, true)
  20 local string = token(l.STRING, sq_str + dq_str + label)
  21
  22 -- Numbers.
  23 local dec = l.digit^1 * ('_' * l.digit^1)^0
  24 local oct_num = '0' * S('01234567_')^1
  25 local integer = S('+-')^-1 * (l.hex_num + oct_num + dec)
  26 local number = token(l.NUMBER, (l.float + integer))
  27
  28 -- Keywords.
  29 local keyword = token(l.KEYWORD, word_match{
  30   'true', 'false', 'on', 'off', 'yes', 'no'
  31 })
  32
  33 -- Identifiers.
  34 local word = (l.alpha + '_') * (l.alnum + S('_.'))^0
  35 local identifier = token(l.IDENTIFIER, word)
  36
  37 -- Operators.
  38 local operator = token(l.OPERATOR, '=')
  39
  40 M._rules = {
  41   {'whitespace', ws},
  42   {'keyword', keyword},
  43   {'identifier', identifier},
  44   {'string', string},
  45   {'comment', comment},
  46   {'number', number},
  47   {'operator', operator},
  48 }
  49
  50 M._LEXBYLINE = true
  51
  52 return M