blob: 9b224455e8a78f0eaf413bfb197d3172dd2bff61 (
plain) (
blame)
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
|
--
-- Haddock - A Haskell Documentation Tool
--
-- (c) Simon Marlow 2002
--
module HaddockLex (
Token(..),
tokenise
) where
import IOExts --tmp
import Char
special = "\'\"/[]"
data Token
= TokPara
| TokNumber
| TokBullet
| TokSpecial Char
| TokString String
deriving Show
-- simple finite-state machine for tokenising the doc string
tokenise :: String -> [Token]
tokenise "" = []
tokenise str = case str of
c:cs | c `elem` special -> TokSpecial c : tokenise cs
'\n':cs -> tokenise_newline cs
_other -> tokenise_string "" str
tokenise_newline cs =
case dropWhile nonNewlineSpace cs of
'\n':cs -> TokPara : tokenise_para cs -- paragraph break
_other -> tokenise_string "\n" cs
tokenise_para cs =
case dropWhile nonNewlineSpace cs of
-- bullet: '*'
'*':cs -> TokBullet : tokenise cs
-- bullet: '-'
'-':cs -> TokBullet : tokenise cs
-- enumerated item: '1.'
str | (ds,'.':cs) <- span isDigit str, not (null ds)
-> TokNumber : tokenise cs
-- enumerated item: '(1)'
'(':cs | (ds,')':cs') <- span isDigit cs, not (null ds)
-> TokNumber : tokenise cs'
other -> tokenise cs
nonNewlineSpace c = isSpace c && c /= '\n'
tokenise_string str cs =
case cs of
[] -> [TokString (reverse str)]
'\\':c:cs -> tokenise_string (c:str) cs
'\n':cs -> tokenise_string_newline str cs
c:cs | c `elem` special -> TokString (reverse str) : tokenise (c:cs)
| otherwise -> tokenise_string (c:str) cs
tokenise_string_newline str cs =
case dropWhile nonNewlineSpace cs of
'\n':cs -> TokString (reverse str) : TokPara : tokenise_para cs
_other -> tokenise_string ('\n':str) cs -- don't throw away whitespace
|
