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
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
-----------------------------------------------------------------------------
-- |
-- Module : Haddock.Interface.ParseModuleHeader
-- Copyright : (c) Simon Marlow 2006, Isaac Dupree 2009
-- License : BSD-like
--
-- Maintainer : haddock@projects.haskell.org
-- Stability : experimental
-- Portability : portable
-----------------------------------------------------------------------------
module Haddock.Interface.ParseModuleHeader (parseModuleHeader) where
import Haddock.Types
import Haddock.Interface.Lex
import Haddock.Interface.Parse
import RdrName
import Data.Char
-- -----------------------------------------------------------------------------
-- Parsing module headers
-- NB. The headers must be given in the order Module, Description,
-- Copyright, License, Maintainer, Stability, Portability, except that
-- any or all may be omitted.
parseModuleHeader :: String -> Either String (HaddockModInfo RdrName, Doc RdrName)
parseModuleHeader str0 =
let
getKey :: String -> String -> (Maybe String,String)
getKey key str = case parseKey key str of
Nothing -> (Nothing,str)
Just (value,rest) -> (Just value,rest)
(_moduleOpt,str1) = getKey "Module" str0
(descriptionOpt,str2) = getKey "Description" str1
(_copyrightOpt,str3) = getKey "Copyright" str2
(_licenseOpt,str4) = getKey "License" str3
(_licenceOpt,str5) = getKey "Licence" str4
(maintainerOpt,str6) = getKey "Maintainer" str5
(stabilityOpt,str7) = getKey "Stability" str6
(portabilityOpt,str8) = getKey "Portability" str7
description1 :: Either String (Maybe (Doc RdrName))
description1 = case descriptionOpt of
Nothing -> Right Nothing
Just description -> case parseHaddockString . tokenise $ description of
Nothing -> Left ("Cannot parse Description: " ++ description)
Just doc -> Right (Just doc)
in
case description1 of
Left mess -> Left mess
Right docOpt -> case parseHaddockParagraphs . tokenise $ str8 of
Nothing -> Left "Cannot parse header documentation paragraphs"
Just doc -> Right (HaddockModInfo {
hmi_description = docOpt,
hmi_portability = portabilityOpt,
hmi_stability = stabilityOpt,
hmi_maintainer = maintainerOpt
}, doc)
-- | This function is how we read keys.
--
-- all fields in the header are optional and have the form
--
-- [spaces1][field name][spaces] ":"
-- [text]"\n" ([spaces2][space][text]"\n" | [spaces]"\n")*
-- where each [spaces2] should have [spaces1] as a prefix.
--
-- Thus for the key "Description",
--
-- > Description : this is a
-- > rather long
-- >
-- > description
-- >
-- > The module comment starts here
--
-- the value will be "this is a .. description" and the rest will begin
-- at "The module comment".
parseKey :: String -> String -> Maybe (String,String)
parseKey key toParse0 =
do
let
(spaces0,toParse1) = extractLeadingSpaces toParse0
indentation = spaces0
afterKey0 <- extractPrefix key toParse1
let
afterKey1 = extractLeadingSpaces afterKey0
afterColon0 <- case snd afterKey1 of
':':afterColon -> return afterColon
_ -> Nothing
let
(_,afterColon1) = extractLeadingSpaces afterColon0
return (scanKey True indentation afterColon1)
where
scanKey :: Bool -> String -> String -> (String,String)
scanKey _ _ [] = ([],[])
scanKey isFirst indentation str =
let
(nextLine,rest1) = extractNextLine str
accept = isFirst || sufficientIndentation || allSpaces
sufficientIndentation = case extractPrefix indentation nextLine of
Just (c:_) | isSpace c -> True
_ -> False
allSpaces = case extractLeadingSpaces nextLine of
(_,[]) -> True
_ -> False
in
if accept
then
let
(scanned1,rest2) = scanKey False indentation rest1
scanned2 = case scanned1 of
"" -> if allSpaces then "" else nextLine
_ -> nextLine ++ "\n" ++ scanned1
in
(scanned2,rest2)
else
([],str)
extractLeadingSpaces :: String -> (String,String)
extractLeadingSpaces [] = ([],[])
extractLeadingSpaces (s@(c:cs))
| isSpace c =
let
(spaces1,cs1) = extractLeadingSpaces cs
in
(c:spaces1,cs1)
| True = ([],s)
extractNextLine :: String -> (String,String)
extractNextLine [] = ([],[])
extractNextLine (c:cs)
| c == '\n' =
([],cs)
| True =
let
(line,rest) = extractNextLine cs
in
(c:line,rest)
-- comparison is case-insensitive.
extractPrefix :: String -> String -> Maybe String
extractPrefix [] s = Just s
extractPrefix _ [] = Nothing
extractPrefix (c1:cs1) (c2:cs2)
| toUpper c1 == toUpper c2 = extractPrefix cs1 cs2
| True = Nothing
|