[racket] Highlighting in DrRacket

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Mon Feb 7 19:42:03 EST 2011

[ I'm not really sure what to do about some of your comments, so I"ve
just replied to a few of them below. Not that I plan to ignore the
others, but until a good solution becomes available, I'll just think
about it. ]

On Mon, Feb 7, 2011 at 6:28 PM, Don Blaheta <dblaheta at monm.edu> wrote:
> Second, the black-on-pink highlighting.  This is how DrRacket indicates
> code that may or may not be the location of a syntax error.  I'm aware
> that this aspect of the editor is an active area of research, so I won't
> comment on *what* is getting pinked.  The problem here is that the pink
> goes away while you're looking at it.  I can make some guesses as to why
> you might have made the pink highlighting time-out, but I can attest
> that it's very annoying to be having a student narrate a problem, or to
> be discussing a problem with them, and have the thing I'm referring to
> just unhighlight itself.  I then have to re-run everything, which is
> a bit annoying, and then kill any of the big-bangs that have been run
> within the definitions, which is more annoying, and then we've
> completely lost our train of thought.  Which is frustrating *and*
> annoying.

There is no timeout. But it does go away if you edit the behavior. At
least that's what I've implemented, if you can make something else
happen, pls. let me know how to too.

> I'd prefer if there were a "clear error highlighting" button somewhere,
> for people that want to get rid of the pink, and it doesn't disappear
> based only on time passing.  (I don't have any problem with it going
> away due to editing the file.)

There is a menu item for that.

> Finally, the pink-on-blue highlighting that marks a true selection.
> In every other program on multiple OSes that I have tried this on, if I
> double-click and then drag or triple-click and then drag, it does
> highlight the word or line/paragraph (respectively) at first, but then
> the drag extends the selection.  In DrRacket, it just locks in at the
> originally-selected ident or line.  It'd be nifty if double-click-drag
> caused select-whole-words behaviour and triple-click-drag caused
> select-whole-lines, but I'd settle for the drag just extending the
> selection on an individual-character basis (just like a regular
> click-drag).  Or is there some downside to this?

I think you're using Windows? (If so, this highlighting is less ugly
in the soon-to-be-released version).

Single click and drag does extend the selection for me.


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