Hi all,
I have recently picked up Scheme and would like to customize the key
bindings in DrScheme. Specifically, I find the default binding for
commenting and uncommenting out to be cumbersome; on OSX it is esc;c:= and
esc;c:semicolon.
What I would like to achieve is use one key to comment and uncomment, so it
comments an uncommented line, and vice versa. Unfortunately I'm finding the
documentation on key-binding a little sparse. Here's what I've been working
at:
(define get-start-of-line
(lambda (editor)
(send editor get-character (send editor line-start-position
(send editor position-line (send editor get-start-position))))))
(define is-line-commented?
(lambda (editor)
(cond
((eq? ";"
(get-start-of-line editor) )#t)
(else #f))))
(keybinding "d:/" (λ (editor evt) (if (is-line-commented? editor)
(send editor uncomment-selection
(send editor get-start-position))
(send editor comment-out-selection
(send editor get-start-position))
)))
I know it's not very well written; I've only just finished the recursion
section of The Little Schemer. I was going to leave it here, then I had
another look at the documentation and had another go:
(define get-start-of-line
(lambda (editor)
(send editor line-start-position
(send editor position-line (send editor get-start-position)))))
(define get-end-of-line
(lambda (editor)
(send editor line-end-position
(send editor position-line (send editor get-end-position)))))
(define is-line-commented?
(lambda (editor)
(send editor find-string
";" 'forward (get-start-of-line editor) (get-end-of-line
editor))))
(keybinding "d:/" (λ (editor evt) (if (is-line-commented? editor)
(send editor uncomment-selection
(send editor get-start-position))
(send editor comment-out-selection
(send editor get-start-position))
)))
This one actually works, but of course it is clumsy and dumb; it doesn't
work when the caret is at the start of each line, and doesn't know if the
semi-colon is escaped. I'm thrilled anyway. :)
Colin
____________________
Racket Users list:
http://lists.racket-lang.org/users
