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
|
% lhs2TeX --poly UnlitP.lhs > UnlitP.tex
\documentclass{article}
\usepackage[german]{babel}
%-------------------------------= --------------------------------------------
%include lhs2TeX.sty
%include lhs2TeX.fmt
%-------------------------------= --------------------------------------------
\begin{document}
%-------------------------------= --------------------------------------------
\section{\texttt{unlit}}
%-------------------------------= --------------------------------------------
Literate-Skripte, die Bird-Tracks verwenden, in Skripte "uberf"uhren,
die die Pseudo-\TeX-Kommandos \verb|\begin{code}|, \verb|\end{code}|
verwenden. Das Programm realisiert einen einfachen UNIX-Filter.
Synopsis:
%
\begin{verbatim}
unlit
unlit <file>
\end{verbatim}
%-------------------------------= --------------------------------------------
%if code || showModuleHeader
> module Main ( main )
> where
>
> import Char ( isSpace )
> import System ( getArgs )
> import Auxiliaries ( (.>) )
%endif
> data Class = Program LineNo Line
> | Spec LineNo Line
> | Blank LineNo Line
> | Comment LineNo Line
>
> type LineNo = Int
> type Line = String
> beginCode, endCode,
> beginSpec, endSpec :: Line
> beginCode = "\\begin{code}"
> endCode = "\\end\&{code}"
> beginSpec = "\\begin{spec}"
> endSpec = "\\end{spec}"
\NB Damit \verb|"\\end{code}"| nicht das Codesegment beendet, wird ein
Nullstring eingef"ugt: \verb|"\\end\&{code}"|.
> main :: IO ()
> main = do args <- getArgs
> unlit args
>
> unlit [] = getContents >>= (putStr . convert)
> unlit (filePath : _) = readFile filePath >>= (putStr . convert)
Fehlt: Fehlerbehandlung, wenn die Datei nicht vorhanden oder nicht
lesbar ist.
> convert :: String -> String
> convert = lines
> .> zip [1 ..] -- number
> .> map classify
> .> format
> .> unlines
> classify :: (LineNo, Line) -> Class
> classify (n, '>' : s) = Program n (' ' : s)
> classify (n, '<' : s) = Spec n (' ' : s)
> classify (n, s)
> | all isSpace s = Blank n s
> classify (n, s) = Comment n s
Die Formatierung wird mit einem einfachen endlichen Automaten mit f"unf
Zust"anden vorgenommen. Es wird darauf geachtet, da"s die Anzahl der
Zeilen nicht ver"andert wird.
\rightcolumn{52}%
> format :: [Class] -> [Line]
> format [] = []
> format (Program _ a : x) = (beginCode ++ a) : inProgram x
> format (Spec _ a : x) = (beginSpec ++ a) : inSpec x
> format (Blank _ a : x) = inBlank a x
> format (Comment _ a : x) = a : inComment x
\rightcolumn{45}%
\rightcolumn{37}%
> inBlank :: Line -> [Class] -> [Line]
> inBlank a [] = [a]
> inBlank a (Program _ b : x) = beginCode : b : inProgram x
> inBlank a (Spec _ b : x) = beginSpec : b : inSpec x
> inBlank a (Blank _ b : x) = a : inBlank b x
> inBlank a (Comment _ b : x) = a : b : inComment x
\rightcolumn{45}%
\rightcolumn{37}%
> inProgram :: [Class] -> [Line]
> inProgram [] = [endCode]
> inProgram (Program _ a : x) = a : inProgram x
> inProgram (Spec n a : x) = message n "program line" "specification line"
> inProgram (Blank _ a : x) = endCode : format x
> inProgram (Comment n a : x) = message n "program line" "comment"
\rightcolumn{45}%
\rightcolumn{37}%
> inSpec :: [Class] -> [Line]
> inSpec [] = [endSpec]
> inSpec (Program n a : x) = message n "specification line" "program line"
> inSpec (Spec _ a : x) = a : inSpec x
> inSpec (Blank _ a : x) = endSpec : format x
> inSpec (Comment n a : x) = message n "specification line" "comment"
> inComment :: [Class] -> [Line]
> inComment [] = []
> inComment (Program n a : x) = message n "comment" "program line"
> inComment (Spec n a : x) = message n "comment" "specification line"
> inComment (Blank _ a : x) = inBlank a x
> inComment (Comment _ a : x) = a : inComment x
> message :: LineNo -> String -> String -> a
> message n x y = error ("line " ++ show n ++ ": "
> ++ x ++ " next to " ++ y ++ "\n")
\end{document}
|
