1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
-- Copyright 2006-2017 Mitchell mitchell.att.foicica.com. See LICENSE.
-- Latex LPeg lexer.
-- Modified by Brian Schott.
-- Modified by Robert Gieseke.
local l = require('lexer')
local token, word_match = l.token, l.word_match
local P, R, S = lpeg.P, lpeg.R, lpeg.S
local M = {_NAME = 'latex'}
-- Whitespace.
local ws = token(l.WHITESPACE, l.space^1)
-- Comments.
local line_comment = '%' * l.nonnewline^0
local block_comment = '\\begin' * P(' ')^0 * '{comment}' *
(l.any - '\\end' * P(' ')^0 * '{comment}')^0 *
P('\\end' * P(' ')^0 * '{comment}')^-1
-- Note: need block_comment before line_comment or LPeg cannot compile rule.
local comment = token(l.COMMENT, block_comment + line_comment)
-- Sections.
local section = token('section', '\\' * word_match{
'part', 'chapter', 'section', 'subsection', 'subsubsection', 'paragraph',
'subparagraph'
} * P('*')^-1)
-- Math environments.
local math_word = word_match{
'align', 'displaymath', 'eqnarray', 'equation', 'gather', 'math', 'multline'
}
local math_begin_end = (P('begin') + P('end')) * P(' ')^0 *
'{' * math_word * P('*')^-1 * '}'
local math = token('math', '$' + '\\' * (S('[]()') + math_begin_end))
-- LaTeX environments.
local environment = token('environment', '\\' * (P('begin') + P('end')) *
P(' ')^0 *
'{' * l.word * P('*')^-1 * '}')
-- Commands.
local command = token(l.KEYWORD, '\\' * (l.alpha^1 + S('#$&~_^%{}')))
-- Operators.
local operator = token(l.OPERATOR, S('&#{}[]'))
M._rules = {
{'whitespace', ws},
{'comment', comment},
{'math', math},
{'environment', environment},
{'section', section},
{'keyword', command},
{'operator', operator},
}
M._tokenstyles = {
environment = l.STYLE_KEYWORD,
math = l.STYLE_FUNCTION,
section = l.STYLE_CLASS
}
M._foldsymbols = {
_patterns = {'\\[a-z]+', '[{}]', '%%'},
[l.COMMENT] = {
['\\begin'] = 1, ['\\end'] = -1, ['%'] = l.fold_line_comments('%')
},
['environment'] = {['\\begin'] = 1, ['\\end'] = -1},
[l.OPERATOR] = {['{'] = 1, ['}'] = -1}
}
return M
|
