ikarus/scheme/ikarus.pretty-print.ss

572 lines
21 KiB
Scheme

;;; Ikarus Scheme -- A compiler for R6RS Scheme.
;;; Copyright (C) 2006,2007,2008 Abdulaziz Ghuloum
;;;
;;; This program is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License version 3 as
;;; published by the Free Software Foundation.
;;;
;;; This program 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
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program. If not, see <http://www.gnu.org/licenses/>.
(library (ikarus pretty-print)
(export pretty-print pretty-width)
(import
(rnrs hashtables)
(only (ikarus writer) traverse traversal-helpers)
(only (ikarus.pretty-formats) get-fmt)
(except (ikarus) pretty-print pretty-width))
(define (map1ltr f ls)
;;; ltr so that gensym counts get assigned properly
(cond
[(null? ls) '()]
[else
(let ([a (f (car ls))])
(cons a (map1ltr f (cdr ls))))]))
(define pretty-width
(make-parameter 60
(lambda (x)
(unless (and (exact? x) (integer? x) (> x 0))
(die 'pretty-width "invalid argument" x))
x)))
(define (pretty-indent) 1)
(define-struct cbox (length boxes))
(define-struct pbox (length ls last))
(define-struct mbox (length str val))
(define-struct vbox (length prefix ls))
(define-struct fbox (length box* sep*))
(define (box-length x)
(cond
[(string? x) (string-length x)]
[(cbox? x) (cbox-length x)]
[(pbox? x) (pbox-length x)]
[(mbox? x) (mbox-length x)]
[(vbox? x) (vbox-length x)]
[(fbox? x) (fbox-length x)]
[else (die 'boxify "invalid box" x)]))
(define (boxify x h)
(define shared-idx 0)
(define (conc . a*)
(let ([n
(let f ([a* a*] [len 0])
(cond
[(null? a*) len]
[else
(f (cdr a*) (fx+ len (box-length (car a*))))]))])
(make-cbox n a*)))
(define (boxify-list ls)
(define (sum-box* ls)
(cond
[(null? (cdr ls))
(box-length (car ls))]
[else
(fx+ (box-length (car ls))
(fxadd1 (sum-box* (cdr ls))))]))
(define (gensep*-default ls)
(cond
[(null? (cdr ls)) '()]
[else
(cons (pretty-indent) (gensep*-default (cdr ls)))]))
(define (tab-value x)
(cond
[(eq? x 'tab) (pretty-indent)]
[(fixnum? x) x]
[else #f]))
(define (select-alt alt-fmt* ls)
(define (good-match? fmt ls)
(cond
[(not (pair? fmt)) #t]
[(eq? (car fmt) 'read-macro)
(and (unshared-list? ls) (fx= (length ls) 2))]
[else
(let ([a (car fmt)] [fmt (cdr fmt)])
(cond
[(or (eq? a 'tab) (fixnum? a))
(good-match? fmt ls)]
[(and (pair? fmt) (eq? (car fmt) '...))
(and (unshared-list? ls)
(andmap (lambda (x) (good-match? a x)) ls))]
[(and (pair? ls) (not (graphed? ls)))
(and (good-match? a (car ls))
(good-match? fmt (cdr ls)))]
[else #f]))]))
(ormap (lambda (fmt) (and (good-match? fmt ls) fmt))
alt-fmt*))
(define (applicable-formats a alt-fmt*)
(cond
[(and (symbol? a) (get-fmt a)) =>
(lambda (fmt)
(cond
[(and (pair? fmt) (eq? (car fmt) 'alt))
(append alt-fmt* (cdr fmt))]
[else
(append alt-fmt* (list fmt))]))]
[(null? alt-fmt*) #f]
[else alt-fmt*]))
(define (return sep* box*)
(let ([n (sum-box* box*)])
(conc "(" (make-fbox n box* sep*) ")")))
(define (boxify-list ls alt-fmt*)
(let ([a (car ls)])
(cond
[(applicable-formats a alt-fmt*) =>
(lambda (fmt*)
(let ([fmt (select-alt fmt* ls)])
(module (fmt-dots? skip-fmt fmt-tab sub-fmt)
(define (parse-fmt x)
(define (parse-dots tab fmt x)
(cond
[(and (pair? x) (eq? (car x) '...))
(values tab fmt #t (cdr x))]
[else
(values tab fmt #f x)]))
(define (parse-tab tab x)
(cond
[(pair? x)
(parse-dots tab (car x) (cdr x))]
[else (values tab #f #f #f)]))
(cond
[(pair? x)
(let ([a0 (car x)])
(cond
[(eq? a0 'tab)
(parse-tab (pretty-indent) (cdr x))]
[(fixnum? a0)
(parse-tab a0 (cdr x))]
[else (parse-tab #f x)]))]
[else (values (pretty-indent) #f #f #f)]))
(define (fmt-dots? x)
(let-values ([(tab subfmt dots fmt) (parse-fmt x)])
dots))
(define (fmt-tab x)
(let-values ([(tab subfmt dots fmt) (parse-fmt x)])
tab))
(define (sub-fmt x)
(let-values ([(tab subfmt dots fmt) (parse-fmt x)])
subfmt))
(define (skip-fmt x)
(let-values ([(tab subfmt dots fmt) (parse-fmt x)])
fmt)))
(define (boxify/fmt fmt x)
(cond
[(and (pair? fmt) (unshared-list? x))
(boxify-list x
(if (eq? (car fmt) 'alt)
(cdr fmt)
(list fmt)))]
[else (boxify x)]))
(define (read-macro? x)
(and (pair? x) (eq? (car x) 'read-macro)))
(cond
[(read-macro? fmt)
(conc (cdr fmt) (boxify (cadr ls)))]
[(fmt-dots? fmt)
(return (fmt-tab fmt)
(map1ltr (lambda (x) (boxify/fmt (sub-fmt fmt) x))
ls))]
[else
(let ([a (boxify/fmt (sub-fmt fmt) a)])
(let-values ([(sep* ls)
(let f ([fmt (skip-fmt fmt)] [ls (cdr ls)])
(cond
[(null? ls)
(values '() '())]
[(fmt-dots? fmt)
(values (fmt-tab fmt)
(map1ltr
(lambda (x)
(boxify/fmt (sub-fmt fmt) x))
ls))]
[else
(let ([a
(boxify/fmt (sub-fmt fmt)
(car ls))])
(let-values ([(f^ l^)
(f (skip-fmt fmt)
(cdr ls))])
(values (cons (fmt-tab fmt) f^)
(cons a l^))))]))])
(return sep* (cons a ls))))])))]
[else
(return (gensep*-default ls) (map1ltr boxify ls))])))
(boxify-list ls '()))
(define (boxify-pair x)
(define (boxify-cdrs x)
(cond
[(and (pair? x) (not (graphed? x)))
(let ([a (boxify (car x))])
(let-values ([(ls last) (boxify-cdrs (cdr x))])
(values (cons a ls) last)))]
[else
(values '() (boxify x))]))
(let ([a (boxify (car x))])
(let-values ([(ls last) (boxify-cdrs (cdr x))])
(let ([ls (cons a ls)])
(let ([n
(let f ([ls ls] [n 4])
(cond
[(null? ls) n]
[else
(f (cdr ls)
(fx+ (fxadd1 n) (box-length (car ls))))]))])
(make-pbox (fx+ n (box-length last)) ls last))))))
(define (boxify-vector x)
(let ([ls (map1ltr boxify (vector->list x))])
(let ([n
(let f ([ls ls] [n 0])
(cond
[(null? ls) n]
[else
(f (cdr ls) (fx+ n (box-length (car ls))))]))])
(make-vbox (fx+ (fx+ n 2) (vector-length x)) "#" ls))))
(define (boxify-bytevector x)
(define prefix "#vu8")
(let ([ls (map (lambda (x) (number->string x))
(bytevector->u8-list x))])
(let ([len (fold-left (lambda (ac s) (+ 1 ac (string-length s)))
(+ 1 (string-length prefix))
ls)])
(make-vbox len prefix ls))))
(define (graphed? x)
(import traversal-helpers)
(let ([b (hashtable-ref h x #f)])
(let ([b (if (fixnum? b) b (car b))])
(cond
[(cyclic-set? b) #t]
[(shared-set? b) (print-graph)]
[else #f]))))
(define (unshared-list? x)
;;; all cdrs of non-empty list are not-shared?
(and (pair? x)
(let f ([x (cdr x)])
(or (null? x)
(and (pair? x)
(not (graphed? x))
(f (cdr x)))))))
(define (boxify-struct x)
(define (boxify-vanilla-struct x)
(cond
[(let ([rtd (struct-type-descriptor x)])
(and (record-type-descriptor? rtd)
(record-type-opaque? rtd)))
"#<unknown>"]
[else
(let* ([name (boxify (struct-name x))]
[ls
(let ([n (struct-length x)])
(let f ([i 0])
(cond
[(fx= i n) '()]
[else
(let ([a (boxify (struct-ref x i))])
(cons a (f (+ i 1))))])))]
[ls (cons name ls)]
[len (fold-left (lambda (ac s) (+ 1 ac (box-length s)))
-1 ls)])
(conc "#[" (make-fbox len ls #f) "]"))]))
(define (boxify-custom-struct out)
(import traversal-helpers)
(let ([ls
(let f ([cache (cdr out)])
(cond
[(not cache) (list (car out))]
[else
(let ([obj (boxify (cache-object cache))])
(let ([ls (f (cache-next cache))])
(cons* (cache-string cache) obj ls)))]))])
(let ([len (fold-left (lambda (ac s) (+ 1 ac (box-length s)))
-1 ls)])
(make-fbox len ls #f))))
(let ([b (hashtable-ref h x #f)])
(cond
[(pair? b) (boxify-custom-struct (cdr b))]
[else (boxify-vanilla-struct x)])))
(define (boxify-shared x k)
(import traversal-helpers)
(let ([b (hashtable-ref h x #f)])
(let ([b (if (fixnum? b) b (car b))])
(cond
[(mark-set? b)
(string-append "#"
(number->string (fxsra b mark-shift))
"#")]
[(or (cyclic-set? b)
(and (shared-set? b) (print-graph)))
(let ([n shared-idx])
(set! shared-idx (+ shared-idx 1))
(set-mark! x h n)
(let ([str (string-append "#" (number->string n) "=")])
(let ([xbox (k x)])
(make-cbox (+ (string-length str) (box-length xbox))
(list str xbox)))))]
[else (k x)]))))
(define (boxify x)
(cond
[(null? x) "()"]
[(vector? x) (boxify-shared x boxify-vector)]
[(unshared-list? x) (boxify-shared x boxify-list)]
[(pair? x) (boxify-shared x boxify-pair)]
[(bytevector? x) (boxify-shared x boxify-bytevector)]
[(struct? x) (boxify-shared x boxify-struct)]
;[(setbox? x)
; (let ([i (format "#~a=" (setbox-idx x))]
; [b (boxify (setbox-data x))])
; (make-cbox (+ (string-length i) (box-length b))
; (list i b)))]
;[(refbox? x) (format "#~a#" (refbox-idx x))]
[else (format "~s" x)]))
(boxify x))
(define string-esc-table
'((7 . "a")
(8 . "b")
(9 . "t")
(10 . "n")
(11 . "v")
(12 . "f")
(13 . "r")
(34 . "\"")
(92 . "\\")))
(define (hexify n)
(cond
[(fx< n 10) (integer->char (fx+ n (char->integer #\0)))]
[else (integer->char (fx+ (fx- n 10) (char->integer #\A)))]))
(define (output x p)
(define (output-cbox x p col)
(let g ([ls (cbox-boxes x)] [p p] [col col])
(cond
[(null? ls) col]
[else
(g (cdr ls) p
(f (car ls) p col))])))
(define (tab col p)
(newline p)
(let f ([col col] [p p])
(unless (fxzero? col)
(display #\space p)
(f (fxsub1 col) p))))
(define (output-pbox x p col)
(define (pbox-one-line x p col)
(display "(" p)
(let g ([ls (pbox-ls x)]
[p p]
[col (fx+ col 1)]
[last (pbox-last x)])
(cond
[(null? ls)
(display ". " p)
(let ([col (f last p (fx+ col 2))])
(display ")" p)
(fx+ col 1))]
[else
(let ([col (f (car ls) p col)])
(display " " p)
(g (cdr ls) p (fx+ col 1) last))])))
(define (pbox-multi-fill x p col)
(display "(" p)
(let g ([ls (cdr (pbox-ls x))]
[p p]
[start-col (fx+ col 1)]
[col (f (car (pbox-ls x)) p (fx+ col 1))]
[last (pbox-last x)])
(cond
[(null? ls)
(let ([n (box-length last)])
(let ([col
(cond
[(fx<= (fx+ (fx+ col n) 4) (pretty-width))
(display " . " p)
(fx+ col 3)]
[else
(tab start-col p)
(display ". " p)
(fx+ start-col 2)])])
(let ([col (f last p col)])
(display ")" p)
(fx+ col 1))))]
[(fx<= (fx+ (fx+ col 1) (box-length (car ls)))
(pretty-width))
(display " " p)
(g (cdr ls) p start-col
(f (car ls) p (fx+ col 1))
last)]
[else
(tab start-col p)
(g (cdr ls) p start-col
(f (car ls) p start-col)
last)])))
(cond
[(fx<= (fx+ col (pbox-length x)) (pretty-width))
(pbox-one-line x p col)]
[else
(pbox-multi-fill x p col)]))
(define (output-mbox x p col)
(display (mbox-str x) p)
(f (mbox-val x) p (fx+ col (string-length (mbox-str x)))))
(define (output-vbox x p col)
(display (vbox-prefix x) p)
(let ([ls (vbox-ls x)] [col (+ col (string-length (vbox-prefix x)))])
(cond
[(null? ls)
(display "()" p)
(fx+ col 2)]
[else
(display "(" p)
(let g ([ls (cdr ls)] [p p]
[col (f (car ls) p (fx+ col 1))]
[start (fx+ col 1)])
(cond
[(null? ls)
(display ")" p)
(fx+ col 1)]
[(fx<= (fx+ (fx+ col 1) (box-length (car ls))) (pretty-width))
(display " " p)
(g (cdr ls) p
(f (car ls) p (fx+ col 1))
start)]
[else
(tab start p)
(g (cdr ls) p
(f (car ls) p start)
start)]))])))
(define (output-fbox x p col)
(define (output-rest-cont box* sep* p col left)
(cond
[(null? box*) col]
[(pair? sep*)
(let* ([box (car box*)]
[sep (car sep*)]
[w (box-length box)])
(cond
[(fx<= (fx+ (fxadd1 w) col) (pretty-width))
(display " " p)
(output-rest-cont (cdr box*) (cdr sep*) p
(f box p (fxadd1 col)) left)]
[(not sep)
(display " " p)
(output-rest-multi (cdr box*) (cdr sep*) p
(f box p (fxadd1 col)) left)]
[else
(let ([col (fx+ left sep)])
(tab col p)
(cond
[(fx<= (fx+ w col) (pretty-width))
(output-rest-cont (cdr box*) (cdr sep*) p
(f box p col) left)]
[else
(output-rest-multi (cdr box*) (cdr sep*) p
(f box p col) left)]))]))]
[else
(output-last-cont box* sep* p col left)]))
(define (output-last-cont box* sep p col left)
(define (sum ls)
(cond
[(null? ls) 0]
[else (fx+ (box-length (car ls))
(fxadd1 (sum (cdr ls))))]))
(cond
[(not sep)
(output-rest-cont box* '(#f . #f) p col left)]
[(fx<= (fx+ (sum box*) col) (pretty-width))
(let g ([box* box*] [p p] [col col])
(cond
[(null? box*) col]
[else
(display " " p)
(g (cdr box*) p (f (car box*) p (fxadd1 col)))]))]
[else
(let g ([box* box*] [p p] [left (fx+ left sep)] [col col])
(cond
[(null? box*) col]
[else
(tab left p)
(g (cdr box*) p left
(f (car box*) p left))]))]))
(define (output-last-multi box* sep p col left)
(define (sum ls)
(cond
[(null? ls) 0]
[else (fx+ (box-length (car ls))
(fxadd1 (sum (cdr ls))))]))
(cond
[(not sep)
(output-rest-multi box* '(#f . #f) p col left)]
[else
(let g ([box* box*] [p p] [left (fx+ left sep)] [col col])
(cond
[(null? box*) col]
[else
(tab left p)
(g (cdr box*) p left
(f (car box*) p left))]))]))
(define (output-rest-multi box* sep* p col left)
(cond
[(null? box*) col]
[(pair? sep*)
(let* ([box (car box*)]
[sep (car sep*)]
[w (box-length box)])
(cond
[(not sep)
(display " " p)
(output-rest-multi (cdr box*) (cdr sep*) p
(f box p (fxadd1 col)) left)]
[else
(let ([col (fx+ left sep)])
(tab col p)
(cond
[(fx<= (fx+ w col) (pretty-width))
(output-rest-cont (cdr box*) (cdr sep*) p
(f box p col) left)]
[else
(output-rest-multi (cdr box*) (cdr sep*) p
(f box p col) left)]))]))]
[else (output-last-multi box* sep* p col left)]))
(define (output-box-init box box* sep* p left)
(let ([w (box-length box)])
(cond
[(fx<= (fx+ w left) (pretty-width))
(let ([col (f box p left)])
(output-rest-cont box* sep* p col left))]
[else
(let ([col (f box p left)])
(output-rest-multi box* sep* p col left))])))
(let ([box* (fbox-box* x)]
[sep* (fbox-sep* x)])
(output-box-init (car box*) (cdr box*) sep* p col)))
(define (f x p col)
(cond
[(string? x)
(display x p)
(fx+ col (string-length x))]
[(cbox? x) (output-cbox x p col)]
[(pbox? x) (output-pbox x p col)]
[(mbox? x) (output-mbox x p col)]
[(vbox? x) (output-vbox x p col)]
[(fbox? x) (output-fbox x p col)]
[else (die 'pretty-print-output "invalid" x)]))
(f x p 0)
(newline p))
;;;
(define (pretty x p)
(let ([h (make-eq-hashtable)])
(traverse x h)
(output (boxify x h) p)))
;;;
(define pretty-print
(case-lambda
[(x) (pretty x (current-output-port))]
[(x p)
(if (output-port? p)
(pretty x p)
(die 'pretty-print "not an output port" p))]))
)