lua/lexers/rstats.lua

   1 -- Copyright 2006-2017 Mitchell mitchell.att.foicica.com. See LICENSE.
   2 -- R 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 = 'rstats'}
   9
  10 -- Whitespace.
  11 local ws = token(l.WHITESPACE, l.space^1)
  12
  13 -- Comments.
  14 local comment = token(l.COMMENT, '#' * l.nonnewline^0)
  15
  16 -- Strings.
  17 local sq_str = l.delimited_range("'", true)
  18 local dq_str = l.delimited_range('"', true)
  19 local string = token(l.STRING, sq_str + dq_str)
  20
  21 -- Numbers.
  22 local number = token(l.NUMBER, (l.float + l.integer) * P('i')^-1)
  23
  24 -- Keywords.
  25 local keyword = token(l.KEYWORD, word_match{
  26   'break', 'else', 'for', 'if', 'in', 'next', 'repeat', 'return', 'switch',
  27   'try', 'while', 'Inf', 'NA', 'NaN', 'NULL', 'FALSE', 'TRUE'
  28 })
  29
  30 -- Types.
  31 local type = token(l.TYPE, word_match{
  32   'array', 'character', 'complex', 'data.frame', 'double', 'factor', 'function',
  33   'integer', 'list', 'logical', 'matrix', 'numeric', 'vector'
  34 })
  35
  36 -- Identifiers.
  37 local identifier = token(l.IDENTIFIER, l.word)
  38
  39 -- Operators.
  40 local operator = token(l.OPERATOR, S('<->+*/^=.,:;|$()[]{}'))
  41
  42 M._rules = {
  43   {'whitespace', ws},
  44   {'keyword', keyword},
  45   {'type', type},
  46   {'identifier', identifier},
  47   {'string', string},
  48   {'comment', comment},
  49   {'number', number},
  50   {'operator', operator},
  51 }
  52
  53 return M