[racket] How to get paren highlighting with online compilation highlighting too?

From: Grant Rettke (grettke at acm.org)
Date: Thu Nov 29 11:04:26 EST 2012

On Thu, Nov 29, 2012 at 7:59 AM, Robby Findler
<robby at eecs.northwestern.edu> wrote:
> The way those highlights work, you are going to see either one or the
> other and I think it gets more confusing when the paren highlights
> obscure the error highlights (indeed, we have had PRs in the past
> claiming that the error highlighting was broken when the priorities
> were reversed).
> Unless you have an idea on how to show both?

What I was thinking was doing something like this:
1. Say there is a section that is highlighted like this (foo (bar
(baz))) ;; (this is not complicated but imagine that it is)
2. The highlighter is highlighting the whole in ERR_COLOR.
3. And you need to fix something and you need to put the cursor in the
right place. Of course I can't reproduce the situation that made me
think of this hence the simple example. Anyway you want paren
4. There is a some color already defined for highlighting matching
parens MP_COLOR. Error highlighting won't use this.
5. Instead it would make MP_ERR_COLOR which is ERR_COLOR but take down
the value (the V in HSV I looked it up) so that it is still clearly an
error, but there is some visual distinction.

Maybe this is an edge case? I can't even create a situation where this
makes sense.

But anyway the idea is that it is clearly an error, but there is a
subtle difference to see paren background highlighting.

Just an idea. I would code it up but it would take me a week. That
said I would be happy to try.

Posted on the users mailing list.