lexers/smalltalk.lua

   1 -- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- Smalltalk 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 = 'smalltalk'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local comment = token(l.COMMENT, l.delimited_range('"', false, true))
  15
  16 -- Strings.
  17 local sq_str = l.delimited_range("'")
  18 local literal = '$' * l.word
  19 local string = token(l.STRING, sq_str + literal)
  20
  21 -- Numbers.
  22 local number = token(l.NUMBER, l.float + l.integer)
  23
  24 -- Keywords.
  25 local keyword = token(l.KEYWORD, word_match{
  26   'true', 'false', 'nil', 'self', 'super', 'isNil', 'not', 'Smalltalk',
  27   'Transcript'
  28 })
  29
  30 -- Types.
  31 local type = token(l.TYPE, word_match{
  32   'Date', 'Time', 'Boolean', 'True', 'False', 'Character', 'String', 'Array',
  33   'Symbol', 'Integer', 'Object'
  34 })
  35
  36 -- Identifiers.
  37 local identifier = token(l.IDENTIFIER, l.word)
  38
  39 -- Operators.
  40 local operator = token(l.OPERATOR, S(':=_<>+-/*!()[]'))
  41
  42 -- Labels.
  43 local label = token(l.LABEL, '#' * l.word)
  44
  45 M._rules = {
  46   {'whitespace', ws},
  47   {'keyword', keyword},
  48   {'type', type},
  49   {'identifier', identifier},
  50   {'string', string},
  51   {'comment', comment},
  52   {'number', number},
  53   {'label', label},
  54   {'operator', operator},
  55 }
  56
  57 M._foldsymbols = {
  58   _patterns = {'[%[%]]'},
  59   [l.OPERATOR] = {['['] = 1, [']'] = -1}
  60 }
  61
  62 return M