basic HAML lexer for TextAdept

haml.lua

-- Copyright 2006-2015 Mitchell mitchell.att.foicica.com. See LICENSE.
-- HAML LPeg lexer.

local l = require('lexer')
local token, word_match = l.token, l.word_match
local P, R, S, V = lpeg.P, lpeg.R, lpeg.S, lpeg.V

local M = {_NAME = 'haml'}

-- Whitespace.
local ws = token(l.WHITESPACE, l.space^1)

-- Comments.
local block_comment = '/' * (l.any - '%')^0
local comment = token(l.COMMENT, block_comment)

-- Strings.
local sq_str = l.delimited_range("'")
local dq_str = l.delimited_range('"')
local string = token(l.STRING, sq_str + dq_str)

-- Numbers.
local number = token(l.NUMBER, l.digit^1)

-- Keywords.
local keyword = token(l.KEYWORD, S('%') * l.alpha * (l.alnum + S('_-'))^0)

-- Identifiers.
local identifier = token(l.IDENTIFIER, l.alpha * (l.alnum + S('_-'))^0)

-- Operators.
local operator = token(l.OPERATOR, S('~!#*>+=|.,:;()[]{}'))

M._rules = {
  {'whitespace', ws},
  {'keyword', keyword},
  {'identifier', identifier},
  {'string', string},
  {'comment', comment},
  {'number', number},
  {'operator', operator},
}

--M._FOLDBYINDENTATION = true

return M