lexers/objective_c.lua

   1 -- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- Objective C 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 = 'objective_c'}
   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 = P('L')^-1 * l.delimited_range("'", true)
  20 local dq_str = P('L')^-1 * l.delimited_range('"', true)
  21 local string = token(l.STRING, sq_str + dq_str)
  22
  23 -- Numbers.
  24 local number = token(l.NUMBER, l.float + l.integer)
  25
  26 -- Preprocessor.
  27 local preproc_word = word_match{
  28   'define', 'elif', 'else', 'endif', 'error', 'if', 'ifdef',
  29   'ifndef', 'import', 'include', 'line', 'pragma', 'undef',
  30   'warning'
  31 }
  32 local preproc = token(l.PREPROCESSOR,
  33                       l.starts_line('#') * S('\t ')^0 * preproc_word *
  34                       (l.nonnewline_esc^1 + l.space * l.nonnewline_esc^0))
  35
  36 -- Keywords.
  37 local keyword = token(l.KEYWORD, word_match({
  38   -- From C.
  39   'asm', 'auto', 'break', 'case', 'const', 'continue', 'default', 'do', 'else',
  40   'extern', 'false', 'for', 'goto', 'if', 'inline', 'register', 'return',
  41   'sizeof', 'static', 'switch', 'true', 'typedef', 'void', 'volatile', 'while',
  42   'restrict', '_Bool', '_Complex', '_Pragma', '_Imaginary',
  43   -- Objective C.
  44   'oneway', 'in', 'out', 'inout', 'bycopy', 'byref', 'self', 'super',
  45   -- Preprocessor directives.
  46   '@interface', '@implementation', '@protocol', '@end', '@private',
  47   '@protected', '@public', '@class', '@selector', '@encode', '@defs',
  48   '@synchronized', '@try', '@throw', '@catch', '@finally',
  49   -- Constants.
  50   'TRUE', 'FALSE', 'YES', 'NO', 'NULL', 'nil', 'Nil', 'METHOD_NULL'
  51 }, '@'))
  52
  53 -- Types.
  54 local type = token(l.TYPE, word_match{
  55   'apply_t', 'id', 'Class', 'MetaClass', 'Object', 'Protocol', 'retval_t',
  56   'SEL', 'STR', 'IMP', 'BOOL', 'TypedStream'
  57 })
  58
  59 -- Identifiers.
  60 local identifier = token(l.IDENTIFIER, l.word)
  61
  62 -- Operators.
  63 local operator = token(l.OPERATOR, S('+-/*%<>!=^&|?~:;.()[]{}'))
  64
  65 M._rules = {
  66   {'whitespace', ws},
  67   {'keyword', keyword},
  68   {'type', type},
  69   {'string', string},
  70   {'identifier', identifier},
  71   {'comment', comment},
  72   {'number', number},
  73   {'preproc', preproc},
  74   {'operator', operator},
  75 }
  76
  77 M._foldsymbols = {
  78   _patterns = {'%l+', '[{}]', '/%*', '%*/', '//'},
  79   [l.PREPROCESSOR] = {
  80     region = 1, endregion = -1,
  81     ['if'] = 1, ifdef = 1, ifndef = 1, endif = -1
  82   },
  83   [l.OPERATOR] = {['{'] = 1, ['}'] = -1},
  84   [l.COMMENT] = {['/*'] = 1, ['*/'] = -1, ['//'] = l.fold_line_comments('//')}
  85 }
  86
  87 return M