Spaces:
Sleeping
Sleeping
File size: 16,211 Bytes
f65fe85 |
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 |
;;;; -*- coding: utf-8; mode: scheme -*-
;;;;
;;;; Copyright (C) 2001, 2004, 2006, 2009, 2010,
;;;; 2012, 2014 Free Software Foundation, Inc.
;;;;
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;;
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;;; Lesser General Public License for more details.
;;;;
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;;;;
(define-module (ice-9 pretty-print)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (rnrs bytevectors)
#:export (pretty-print
truncated-print))
;; From SLIB.
;;"genwrite.scm" generic write used by pretty-print and truncated-print.
;; Copyright (c) 1991, Marc Feeley
;; Author: Marc Feeley ([email protected])
;; Distribution restrictions: none
(define genwrite:newline-str (make-string 1 #\newline))
(define (generic-write
obj display? width max-expr-width per-line-prefix output)
(define (read-macro? l)
(define (length1? l) (and (pair? l) (null? (cdr l))))
(let ((head (car l)) (tail (cdr l)))
(case head
((quote quasiquote unquote unquote-splicing) (length1? tail))
(else #f))))
(define (read-macro-body l)
(cadr l))
(define (read-macro-prefix l)
(let ((head (car l)))
(case head
((quote) "'")
((quasiquote) "`")
((unquote) ",")
((unquote-splicing) ",@"))))
(define (out str col)
(and col (output str) (+ col (string-length str))))
(define (wr obj col)
(let loop ((obj obj)
(col col))
(match obj
(((or 'quote 'quasiquote 'unquote 'unquote-splicing) body)
(wr body (out (read-macro-prefix obj) col)))
((head . (rest ...))
;; A proper list: do our own list printing so as to catch read
;; macros that appear in the middle of the list.
(let ((col (loop head (out "(" col))))
(out ")"
(fold (lambda (i col)
(loop i (out " " col)))
col rest))))
(_
(out (object->string obj (if display? display write)) col)))))
(define (pp obj col)
(define (spaces n col)
(if (> n 0)
(if (> n 7)
(spaces (- n 8) (out " " col))
(out (substring " " 0 n) col))
col))
(define (indent to col)
(and col
(if (< to col)
(and (out genwrite:newline-str col)
(out per-line-prefix 0)
(spaces to 0))
(spaces (- to col) col))))
(define (pr obj col extra pp-pair)
(if (or (pair? obj) (vector? obj)) ; may have to split on multiple lines
(let ((result '())
(left (min (+ (- (- width col) extra) 1) max-expr-width)))
(generic-write obj display? #f max-expr-width ""
(lambda (str)
(set! result (cons str result))
(set! left (- left (string-length str)))
(> left 0)))
(if (> left 0) ; all can be printed on one line
(out (reverse-string-append result) col)
(if (pair? obj)
(pp-pair obj col extra)
(pp-list (vector->list obj) (out "#" col) extra pp-expr))))
(wr obj col)))
(define (pp-expr expr col extra)
(if (read-macro? expr)
(pr (read-macro-body expr)
(out (read-macro-prefix expr) col)
extra
pp-expr)
(let ((head (car expr)))
(if (symbol? head)
(let ((proc (style head)))
(if proc
(proc expr col extra)
(if (> (string-length (symbol->string head))
max-call-head-width)
(pp-general expr col extra #f #f #f pp-expr)
(pp-call expr col extra pp-expr))))
(pp-list expr col extra pp-expr)))))
; (head item1
; item2
; item3)
(define (pp-call expr col extra pp-item)
(let ((col* (wr (car expr) (out "(" col))))
(and col
(pp-down (cdr expr) col* (+ col* 1) extra pp-item))))
; (item1
; item2
; item3)
(define (pp-list l col extra pp-item)
(let ((col (out "(" col)))
(pp-down l col col extra pp-item)))
(define (pp-down l col1 col2 extra pp-item)
(let loop ((l l) (col col1))
(and col
(cond ((pair? l)
(let ((rest (cdr l)))
(let ((extra (if (null? rest) (+ extra 1) 0)))
(loop rest
(pr (car l) (indent col2 col) extra pp-item)))))
((null? l)
(out ")" col))
(else
(out ")"
(pr l
(indent col2 (out "." (indent col2 col)))
(+ extra 1)
pp-item)))))))
(define (pp-general expr col extra named? pp-1 pp-2 pp-3)
(define (tail1 rest col1 col2 col3)
(if (and pp-1 (pair? rest))
(let* ((val1 (car rest))
(rest (cdr rest))
(extra (if (null? rest) (+ extra 1) 0)))
(tail2 rest col1 (pr val1 (indent col3 col2) extra pp-1) col3))
(tail2 rest col1 col2 col3)))
(define (tail2 rest col1 col2 col3)
(if (and pp-2 (pair? rest))
(let* ((val1 (car rest))
(rest (cdr rest))
(extra (if (null? rest) (+ extra 1) 0)))
(tail3 rest col1 (pr val1 (indent col3 col2) extra pp-2)))
(tail3 rest col1 col2)))
(define (tail3 rest col1 col2)
(pp-down rest col2 col1 extra pp-3))
(let* ((head (car expr))
(rest (cdr expr))
(col* (wr head (out "(" col))))
(if (and named? (pair? rest))
(let* ((name (car rest))
(rest (cdr rest))
(col** (wr name (out " " col*))))
(tail1 rest (+ col indent-general) col** (+ col** 1)))
(tail1 rest (+ col indent-general) col* (+ col* 1)))))
(define (pp-expr-list l col extra)
(pp-list l col extra pp-expr))
(define (pp-LAMBDA expr col extra)
(pp-general expr col extra #f pp-expr-list #f pp-expr))
(define (pp-IF expr col extra)
(pp-general expr col extra #f pp-expr #f pp-expr))
(define (pp-COND expr col extra)
(pp-call expr col extra pp-expr-list))
(define (pp-CASE expr col extra)
(pp-general expr col extra #f pp-expr #f pp-expr-list))
(define (pp-AND expr col extra)
(pp-call expr col extra pp-expr))
(define (pp-LET expr col extra)
(let* ((rest (cdr expr))
(named? (and (pair? rest) (symbol? (car rest)))))
(pp-general expr col extra named? pp-expr-list #f pp-expr)))
(define (pp-BEGIN expr col extra)
(pp-general expr col extra #f #f #f pp-expr))
(define (pp-DO expr col extra)
(pp-general expr col extra #f pp-expr-list pp-expr-list pp-expr))
(define (pp-SYNTAX-CASE expr col extra)
(pp-general expr col extra #t pp-expr-list #f pp-expr))
; define formatting style (change these to suit your style)
(define indent-general 2)
(define max-call-head-width 5)
(define (style head)
(case head
((lambda lambda* let* letrec define define* define-public
define-syntax let-syntax letrec-syntax with-syntax)
pp-LAMBDA)
((if set!) pp-IF)
((cond) pp-COND)
((case) pp-CASE)
((and or) pp-AND)
((let) pp-LET)
((begin) pp-BEGIN)
((do) pp-DO)
((syntax-rules) pp-LAMBDA)
((syntax-case) pp-SYNTAX-CASE)
(else #f)))
(pr obj col 0 pp-expr))
(out per-line-prefix 0)
(if width
(out genwrite:newline-str (pp obj 0))
(wr obj 0))
;; Return `unspecified'
(if #f #f))
; (reverse-string-append l) = (apply string-append (reverse l))
(define (reverse-string-append l)
(define (rev-string-append l i)
(if (pair? l)
(let* ((str (car l))
(len (string-length str))
(result (rev-string-append (cdr l) (+ i len))))
(let loop ((j 0) (k (- (- (string-length result) i) len)))
(if (< j len)
(begin
(string-set! result k (string-ref str j))
(loop (+ j 1) (+ k 1)))
result)))
(make-string i)))
(rev-string-append l 0))
(define* (pretty-print obj #:optional port*
#:key
(port (or port* (current-output-port)))
(width 79)
(max-expr-width 50)
(display? #f)
(per-line-prefix ""))
"Pretty-print OBJ on PORT, which is a keyword argument defaulting to
the current output port. Formatting can be controlled by a number of
keyword arguments: Each line in the output is preceded by the string
PER-LINE-PREFIX, which is empty by default. The output lines will be
at most WIDTH characters wide; the default is 79. If DISPLAY? is
true, display rather than write representation will be used.
Instead of with a keyword argument, you can also specify the output
port directly after OBJ, like (pretty-print OBJ PORT)."
(generic-write obj display?
(- width (string-length per-line-prefix))
max-expr-width
per-line-prefix
(lambda (s) (display s port) #t)))
;; `truncated-print' was written in 2009 by Andy Wingo, and is not from
;; genwrite.scm.
(define* (truncated-print x #:optional port*
#:key
(port (or port* (current-output-port)))
(width 79)
(display? #f)
(breadth-first? #f))
"Print @var{x}, truncating the output, if necessary, to make it fit
into @var{width} characters. By default, @var{x} will be printed using
@code{write}, though that behavior can be overriden via the
@var{display?} keyword argument.
The default behaviour is to print depth-first, meaning that the entire
remaining width will be available to each sub-expression of @var{x} --
e.g., if @var{x} is a vector, each member of @var{x}. One can attempt to
\"ration\" the available width, trying to allocate it equally to each
sub-expression, via the @var{breadth-first?} keyword argument."
;; Make sure string ports are created with the right encoding.
(with-fluids ((%default-port-encoding (port-encoding port)))
(define ellipsis
;; Choose between `HORIZONTAL ELLIPSIS' (U+2026) and three dots, depending
;; on the encoding of PORT.
(let ((e "…"))
(catch 'encoding-error
(lambda ()
(with-fluids ((%default-port-conversion-strategy 'error))
(with-output-to-string
(lambda ()
(display e)))))
(lambda (key . args)
"..."))))
(let ((ellipsis-width (string-length ellipsis)))
(define (print-sequence x width len ref next)
(let lp ((x x)
(width width)
(i 0))
(if (> i 0)
(display #\space))
(cond
((= i len)) ; catches 0-length case
((and (= i (1- len)) (or (zero? i) (> width 1)))
(print (ref x i) (if (zero? i) width (1- width))))
((<= width (+ 1 ellipsis-width))
(display ellipsis))
(else
(let ((str
(with-fluids ((%default-port-encoding (port-encoding port)))
(with-output-to-string
(lambda ()
(print (ref x i)
(if breadth-first?
(max 1
(1- (floor (/ width (- len i)))))
(- width (+ 1 ellipsis-width)))))))))
(display str)
(lp (next x) (- width 1 (string-length str)) (1+ i)))))))
(define (print-tree x width)
;; width is >= the width of # . #, which is 5
(let lp ((x x)
(width width))
(cond
((or (not (pair? x)) (<= width 4))
(display ". ")
(print x (- width 2)))
(else
;; width >= 5
(let ((str (with-output-to-string
(lambda ()
(print (car x)
(if breadth-first?
(floor (/ (- width 3) 2))
(- width 4)))))))
(display str)
(display " ")
(lp (cdr x) (- width 1 (string-length str))))))))
(define (truncate-string str width)
;; width is < (string-length str)
(let lp ((fixes '(("#<" . ">")
("#(" . ")")
("(" . ")")
("\"" . "\""))))
(cond
((null? fixes)
"#")
((and (string-prefix? (caar fixes) str)
(string-suffix? (cdar fixes) str)
(>= (string-length str)
width
(+ (string-length (caar fixes))
(string-length (cdar fixes))
ellipsis-width)))
(format #f "~a~a~a~a"
(caar fixes)
(substring str (string-length (caar fixes))
(- width (string-length (cdar fixes))
ellipsis-width))
ellipsis
(cdar fixes)))
(else
(lp (cdr fixes))))))
(define (print x width)
(cond
((<= width 0)
(error "expected a positive width" width))
((list? x)
(cond
((>= width (+ 2 ellipsis-width))
(display "(")
(print-sequence x (- width 2) (length x)
(lambda (x i) (car x)) cdr)
(display ")"))
(else
(display "#"))))
((vector? x)
(cond
((>= width (+ 3 ellipsis-width))
(display "#(")
(print-sequence x (- width 3) (vector-length x)
vector-ref identity)
(display ")"))
(else
(display "#"))))
((bytevector? x)
(cond
((>= width 9)
(format #t "#~a(" (array-type x))
(print-sequence x (- width 6) (array-length x)
array-ref identity)
(display ")"))
(else
(display "#"))))
((pair? x)
(cond
((>= width (+ 4 ellipsis-width))
(display "(")
(print-tree x (- width 2))
(display ")"))
(else
(display "#"))))
(else
(let* ((str (with-output-to-string
(lambda () (if display? (display x) (write x)))))
(len (string-length str)))
(display (if (<= (string-length str) width)
str
(truncate-string str width)))))))
(with-output-to-port port
(lambda ()
(print x width))))))
|