[racket] online check syntax error display tweak

At Fri, 9 Sep 2011 11:20:36 -0500,
Robby Findler wrote:
> 
> On Fri, Sep 9, 2011 at 11:05 AM, Vincent St-Amour <stamourv at ccs.neu.edu> wrote:
> > At Fri, 9 Sep 2011 10:58:23 -0500,
> > Robby Findler wrote:
> >> I thought about that, but I didn't want it to overlap the text and I
> >> didn't want it to slide everything over to make space.
> >
> > What about horizontal lines before and after the relevant line,
> > running across the whole editor. Finding the relevant code becomes a
> > matter of following the lines. Grant Rettke's IntelliJ screenshot does
> > something similar, and I think it helps.
> >
> >> What if there was a keybinding that jumped you to the right place?
> >
> > That would be great too. Emacs uses C-x ` for that.
> 
> How about a keystroke to jump to the place plus it colors things in
> when you mouse over the right thingy in the right margin? If that
> doesn't sound horrible, then I'll push something to try it out.

Sounds good.

Vincent