-
Notifications
You must be signed in to change notification settings - Fork 0
/
util.ss
139 lines (123 loc) · 4.54 KB
/
util.ss
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
(library (util)
(export escape
escape-string
xml-escape
tex-escape
string-escape
count-from-beginning
join-lines
cfb-port
read-until
assert-with-msg
read-until-k
make-list
read-datum-from-file
join
join-path)
(import (rnrs))
(define escape
(lambda (c table)
(let ((r (assq c table)))
(if r
(cdr r)
(string c)))))
(define escape-string
(lambda (s table)
(apply string-append
(map (lambda (c) (escape c table))
(string->list s)))))
(define xml-escape
(lambda (s)
(escape-string s '((#\< . "<")
(#\> . ">")
(#\& . "&")))))
(define tex-escape
(lambda (s)
(escape-string s '((#\# . "\\#")
(#\$ . "\\$")
(#\% . "\\%")
(#\& . "\\&")
(#\{ . "\\{")
(#\} . "\\}")
(#\_ . "\\_")
(#\^ . "\\^{}")
(#\~ . "\\~{}")
(#\\ . "\\textbackslash{}")))))
(define string-escape
(lambda (s)
(escape-string s '((#\newline . "\\n")
(#\" . "\\\"")
(#\\ . "\\\\")))))
(define count-from-beginning
(lambda (line c)
(define cfb-iter
(lambda (line c beginning count)
(if (> (string-length line) beginning)
(if (char=? (string-ref line beginning) c)
(cfb-iter line c (+ beginning 1) (+ count 1))
count)
count)))
(cfb-iter line c 0 0)))
(define cfb-port
(lambda (port c)
(define cfb-port-iter
(lambda (port c count)
(let ((e (lookahead-char port)))
(if (char=? c e)
(begin (get-char port) (cfb-port-iter port c (+ count 1)))
count))))
(cfb-port-iter port c 0)))
(define join-lines
(lambda (lines)
(apply string-append (map (lambda (s) (string-append s (string #\newline))) lines))))
(define read-until
(lambda (port c)
(define read-until-iter
(lambda (port c acc)
(let ((e (lookahead-char port)))
(if (char=? e c)
(apply string (reverse acc))
(read-until-iter port c (cons (read-char port) acc))))))
(read-until-iter port c '())))
(define assert-with-msg
(lambda (p who message . irritants)
(if (not p)
(apply assertion-violation who message irritants))))
(define apply-k
(lambda (proc k arg)
(if (= k 0) arg (proc (apply-k proc (- k 1) arg)))))
(define read-until-k
(lambda (port c k)
(define read-until-k-iter
(lambda (port c k acc count)
(let ((e (lookahead-char port)))
(cond ((= k count) (apply string (reverse (apply-k cdr k acc))))
((eof-object? e) (apply string (reverse acc)))
((char=? e c) (read-until-k-iter port c k (cons (get-char port) acc) (+ count 1)))
(else (read-until-k-iter port c k (cons (get-char port) acc) 0))))))
(read-until-k-iter port c k '() 0)))
(define make-list
(lambda (k fill)
(if (= k 0)
'()
(cons fill (make-list (- k 1) fill)))))
(define read-datum-from-file
(lambda (path)
(let* ((port (open-file-input-port path
(file-options)
'block
(make-transcoder (utf-8-codec))))
(datum (get-datum port)))
(close-input-port port)
datum)))
(define join
(lambda (sep strings)
(cond ((< (length strings) 2) (apply string-append strings))
(else (string-append (car strings) (apply string-append (apply append (map (lambda (s) (list sep s)) (cdr strings)))))))))
(define join-path
(lambda components
(cond ((null? components) ".")
((= (length components) 1) (car components))
(else (string-append (car components)
"/"
(apply join-path (cdr components))))))))