lexers/pico8.lua

   1 -- Copyright 2016 Alejandro Baez (https://keybase.io/baez). See LICENSE.
   2 -- PICO-8 Lexer.
   3 -- http://www.lexaloffle.com/pico-8.php
   4
   5 local l = require('lexer')
   6 local token, word_match = l.token, l.word_match
   7 local P, R, S = lpeg.P, lpeg.R, lpeg.S
   8
   9 local M = {_NAME = 'pico8'}
  10
  11 -- Whitespace
  12 local ws = token(l.WHITESPACE, l.space^1)
  13
  14 -- Comments
  15 local line_comment = '//' * l.nonnewline_esc^0
  16 local comment = token(l.COMMENT, line_comment)
  17
  18 -- Numbers
  19 local number = token(l.NUMBER, l.integer)
  20
  21 -- Keywords
  22 local keyword = token(l.KEYWORD, word_match{
  23   '__lua__', '__gfx__', '__gff__', '__map__', '__sfx__', '__music__'
  24 })
  25
  26 -- Identifiers
  27 local identifier = token(l.IDENTIFIER, l.word)
  28
  29 -- Operators
  30 local operator = token(l.OPERATOR, S('_'))
  31
  32 M._rules = {
  33   {'whitespace', ws},
  34   {'keyword', keyword},
  35   {'identifier', identifier},
  36   {'comment', comment},
  37   {'number', number},
  38   {'operator', operator},
  39 }
  40
  41 -- Embed Lua into PICO-8.
  42 local lua = l.load('lua')
  43
  44 local lua_start_rule = token('pico8_tag', '__lua__')
  45 local lua_end_rule = token('pico8_tag', '__gfx__' )
  46 l.embed_lexer(M, lua, lua_start_rule, lua_end_rule)
  47
  48 M._tokenstyles = {
  49   pico8_tag = l.STYLE_EMBEDDED
  50 }
  51
  52 M._foldsymbols = lua._foldsymbols
  53
  54 return M