aboutsummaryrefslogtreecommitdiffstats
path: root/qp.scm
blob: b772d89eb52641055f699adff8fbbc074073ae54 (plain)
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
;;;; "qp.scm" Print finite length representation for any Scheme object.
;;; Copyright (C) 1991, 1992, 1993, 1995, 2003 Aubrey Jaffer
;
;Permission to copy this software, to modify it, to redistribute it,
;to distribute modified versions, and to use it for any purpose is
;granted, subject to the following restrictions and understandings.
;
;1.  Any copy made of this software must include this copyright notice
;in full.
;
;2.  I have made no warranty or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3.  In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.

;@
(define *qp-width* (output-port-width (current-output-port)))
;@
(define qp
  (let
      ((+ +) (- -) (< <) (= =) (>= >=) (apply apply) (boolean? boolean?)
       (car car) (cdr cdr) (char? char?) (display display) (eq? eq?)
       (for-each for-each) (input-port? input-port?)
       (not not) (null? null?) (number->string number->string)
       (number? number?) (output-port? output-port?) (eof-object? eof-object?)
       (procedure? procedure?) (string-length string-length)
       (string? string?) (substring substring)
       (symbol->string symbol->string) (symbol? symbol?)
       (vector-length vector-length) (vector-ref vector-ref)
       (vector? vector?) (write write) (quotient quotient))
    (letrec
	((num-cdrs
	  (lambda (pairs max-cdrs)
	    (cond
	     ((null? pairs) 0)
	     ((< max-cdrs 1) 1)
	     ((pair? pairs) (+ 1 (num-cdrs (cdr pairs) (- max-cdrs 1))))
	     (else 1))))

	 (l-elt-room
	  (lambda (room pairs)
	    (quotient room (num-cdrs pairs (quotient room 8)))))

	 (qp-pairs
	  (lambda (cdrs room)
	    (cond
	     ((null? cdrs) 0)
	     ((not (pair? cdrs))
	      (display " . ")
	      (+ 3 (qp-obj cdrs (l-elt-room (- room 3) cdrs))))
	     ((< 11 room)
	      (display #\space)
	      ((lambda (used)
		 (+ (qp-pairs (cdr cdrs) (- room used)) used))
	       (+ 1 (qp-obj (car cdrs) (l-elt-room (- room 1) cdrs)))))
	     (else
	      (display " ...") 4))))

	 (v-elt-room
	  (lambda (room vleft)
	    (quotient room (min vleft (quotient room 8)))))

	 (qp-vect
	  (lambda (vect i room)
	    (cond
	     ((= (vector-length vect) i) 0)
	     ((< 11 room)
	      (display #\space)
	      ((lambda (used)
		 (+ (qp-vect vect (+ i 1) (- room used)) used))
	       (+ 1 (qp-obj (vector-ref vect i)
			    (v-elt-room (- room 1)
					(- (vector-length vect) i))))))
	     (else
	      (display " ...") 4))))

	 (qp-string
	  (lambda (str room)
	    (define len (string-length str))
	    (define mid (quotient (- room 3) 2))
	    (cond
	     ((>= len room 3)
	      (display (substring str 0 (- room 3 mid)))
	      (display "...")
	      (display (substring str (- len mid) len))
	      room)
	     (else
	      (display str)
	      len))))

	 (qp-obj
	  (lambda (obj room)
	    (cond
	     ((null? obj) (write obj) 2)
	     ((boolean? obj) (write obj) 2)
	     ((char? obj) (write obj) 8)
	     ((number? obj) (qp-string (number->string obj) room))
	     ((string? obj)
	      (display #\")
	      ((lambda (ans) (display #\") ans)
	       (+ 2 (qp-string obj (- room 2)))))
	     ((symbol? obj) (qp-string (symbol->string obj) room))
	     ((input-port? obj) (display "#[input]") 8)
	     ((output-port? obj) (display "#[output]") 9)
	     ((procedure? obj) (display "#[proc]") 7)
	     ((eof-object? obj) (display "#[eof]") 6)
	     ((vector? obj)
	      (set! room (- room 3))
	      (display "#(")
	      ((lambda (used) (display #\)) (+ used 3))
	       (cond
		((= 0 (vector-length obj)) 0)
		((< room 8) (display "...") 3)
		(else
		 ((lambda (used) (+ (qp-vect obj 1 (- room used)) used))
		  (qp-obj (vector-ref obj 0)
			  (v-elt-room room (vector-length obj))))))))
	     ((pair? obj)
	      (set! room (- room 2))
	      (display #\()
	      ((lambda (used) (display #\)) (+ 2 used))
	       (if (< room 8) (begin (display "...") 3)
		   ((lambda (used)
		      (+ (qp-pairs (cdr obj) (- room used)) used))
		    (qp-obj (car obj) (l-elt-room room obj))))))
	     (else (display "#[unknown]") 10)))))

      (lambda objs
	(cond
	 ((not *qp-width*)
	  (for-each (lambda (x) (write x) (display #\space)) objs)
	  (newline))
	 ((= 0 *qp-width*)
	  (for-each (lambda (x)
		      (if (procedure? x) (display "#[proc]") (write x))
		      (display #\space)) objs))
	 (else
	  (qp-pairs (cdr objs)
		    (- *qp-width*
		       (qp-obj (car objs) (l-elt-room *qp-width* objs))))))))))
;@
(define qpn
  (let ((newline newline) (apply apply))
    (lambda objs (apply qp objs) (newline))))
;@
(define qpr
  (let ((- -) (apply apply) (length length) (list-ref list-ref))
    (lambda objs (apply qpn objs)
	    (list-ref objs (- (length objs) 1)))))