text% printer recognizes a line containing only a form-feed character and uses it as a page break; a form-feed character displays as ^L

original commit: 92a410687731200c8167b29bdcefb7f86c2ead3f
This commit is contained in:
Matthew Flatt 2010-05-11 09:37:08 -06:00
commit b95d39c847

View File

@ -5430,6 +5430,14 @@
(set! write-locked? wl?) (set! write-locked? wl?)
(set! flow-locked? fl?)))) (set! flow-locked? fl?))))
(define/private (new-page-line? line)
(let ([len (mline-len line)])
(and (<= 1 len 2)
(let* ([pos (mline-get-position line)]
[s (get-text pos (+ pos len))])
(or (equal? s "\f")
(equal? s "\f\n"))))))
(define/private (has/print-page dc page print?) (define/private (has/print-page dc page print?)
(if flow-locked? (if flow-locked?
#f #f
@ -5463,15 +5471,25 @@
[next-h 0.0]) [next-h 0.0])
(let loop ([h h] (let loop ([h h]
[i i] [i i]
[line line]) [line line]
(if (or (zero? h) [can-continue? #t]
[unline 0.0])
(cond
[(or (zero? h)
(and (i . < . num-valid-lines) (and (i . < . num-valid-lines)
((mline-h line) . < . (- H h)))) ((mline-h line) . < . (- H h))
(loop (+ h (mline-h line)) can-continue?))
(let ([lh (mline-h line)]
[new-page? (new-page-line? line)])
(loop (+ h lh)
(add1 i) (add1 i)
(mline-next line)) (mline-next line)
(not new-page?)
(if new-page? lh unline)))]
[else
(let-values ([(h i line) (let-values ([(h i line)
(if (and (h . < . H) (cond
[(and (h . < . H)
(i . < . num-valid-lines) (i . < . num-valid-lines)
((mline-h line) . > . H)) ((mline-h line) . > . H))
;; we'll have to break it up anyway; start now? ;; we'll have to break it up anyway; start now?
@ -5482,8 +5500,9 @@
(values (+ h (mline-h line)) (values (+ h (mline-h line))
(add1 i) (add1 i)
(mline-next line)) (mline-next line))
(values h i line))) (values h i line)))]
(values h i line))]) [else
(values h i line)])])
(let-values ([(next-h h) (let-values ([(next-h h)
(if (h . > . H) (if (h . > . H)
;; only happens if we have something that's too big to fit on a page; ;; only happens if we have something that's too big to fit on a page;
@ -5504,7 +5523,7 @@
(send dc start-page)) (send dc start-page))
(do-redraw dc (do-redraw dc
(+ y (if (zero? i) 0 1)) (+ y (if (zero? i) 0 1))
(+ y (- h 1)) (+ y (- h 1 unline))
0 W (+ (- y) vm) hm 0 W (+ (- y) vm) hm
'no-caret #f #f) 'no-caret #f #f)
(when (negative? page) (when (negative? page)
@ -5515,7 +5534,7 @@
line line
(+ y h) (+ y h)
next-h next-h
i))))))))))))))) i))))])))))))))))
(define/override (do-has-print-page? dc page) (define/override (do-has-print-page? dc page)
(has/print-page dc page #f)) (has/print-page dc page #f))