<div dir="ltr"><div>Not considering keybindings, you may also be interested in the various commenting styles, in particular the "#|" and "|#" comments, that comment several lines, and the "#;" comment which, if placed right before an opening parenthesis, comments the following code up to the corresponding closing parenthesis:<br>
<a href="http://docs.racket-lang.org/reference/reader.html?q=%23%3B#%28idx._%28gentag._65._%28lib._scribblings%2Freference%2Freference..scrbl%29%29%29">http://docs.racket-lang.org/reference/reader.html?q=%23%3B#%28idx._%28gentag._65._%28lib._scribblings%2Freference%2Freference..scrbl%29%29%29</a><br>
<br></div>Laurent<br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Mon, Nov 25, 2013 at 2:23 PM, Robby Findler <span dir="ltr"><<a href="mailto:robby@eecs.northwestern.edu" target="_blank">robby@eecs.northwestern.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Nice job!<div><br></div><div>One point where the docs are confusing: "line"s are soft-wrapped, not hard-wrapped lines. For code you want the methods with the word "paragraph" in the name instead of "line".</div>
<div><br></div><div>I'm not seeing why your code doesn't work at the beginning of the line, but if you start up drracket from the command-line and then put printfs into your functions, you should be able to see intermediate values and you can check what's going on. Or, if you're on windows, you might find it easier to call "message-box", ie:</div>
<div><br></div><div><div><div><font face="monospace">(define is-line-commented?</font></div><div><font face="monospace"> (lambda (editor)</font></div><div><font face="monospace"> (define ans</font></div><div class="im">
<div><font face="monospace"> (send editor find-string </font></div>
<div><font face="monospace"> ";" 'forward (get-start-of-line editor) (get-end-of-line editor)))</font></div></div><div><font face="monospace"> (message-box "hi" (format "ans ~s" ans))</font></div>
<div><font face="monospace"> ans))</font></div><div style="font-family:monospace"><br></div></div></div><div style="font-family:monospace">Robby</div><div><br></div><div><br></div></div><div class="gmail_extra"><br><br>
<div class="gmail_quote"><div><div class="h5">On Sat, Nov 23, 2013 at 9:42 AM, Colin Gan <span dir="ltr"><<a href="mailto:gan.colin.e@gmail.com" target="_blank">gan.colin.e@gmail.com</a>></span> wrote:<br></div></div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div class="h5">
<div dir="ltr">Hi all,<div><br></div><div>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.</div>
<div><br></div><div>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:</div>
<div><br></div><div><div><br></div><div><div>(define get-start-of-line</div><div> (lambda (editor)</div><div> (send editor get-character (send editor line-start-position </div><div> (send editor position-line (send editor get-start-position))))))</div>
<div><br></div><div>(define is-line-commented?</div><div> (lambda (editor)</div><div> (cond</div><div> ((eq? ";" </div><div> (get-start-of-line editor) )#t)</div><div> (else #f))))</div>
<div><br></div><div>(keybinding "d:/" (λ (editor evt) (if (is-line-commented? editor) </div><div> (send editor uncomment-selection (send editor get-start-position))</div><div>
(send editor comment-out-selection (send editor get-start-position))</div><div> )))</div></div></div><div><br></div><div><br></div><div>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:</div>
<div><br></div><div><div>(define get-start-of-line</div><div> (lambda (editor)</div><div> (send editor line-start-position </div><div> (send editor position-line (send editor get-start-position)))))</div><div>
<br></div><div>(define get-end-of-line</div><div> (lambda (editor)</div><div> (send editor line-end-position </div><div> (send editor position-line (send editor get-end-position)))))</div><div><br></div><div>
(define is-line-commented?</div><div> (lambda (editor)</div><div> (send editor find-string </div><div> ";" 'forward (get-start-of-line editor) (get-end-of-line editor))))</div><div><br></div>
<div>
<br></div><div>(keybinding "d:/" (λ (editor evt) (if (is-line-commented? editor) </div><div> (send editor uncomment-selection (send editor get-start-position))</div><div> (send editor comment-out-selection (send editor get-start-position))</div>
<div> )))</div></div><div><br></div><div><br></div><div>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. :)</div>
<span><font color="#888888">
<div><br></div><div><br></div><div>Colin</div></font></span></div>
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