On Thu, Sep 10, 2009 at 8:04 PM, Stefan Monnier
<address@hidden> wrote:
> Essentially, I wanted to add echo-area messages to Flymake when the point
> was in a section highlighted as an error. js2-mode does this using text
> properties when it defines overlays, which is another option I could look
> at, but it seems much better to be able to just have an overlay for all of
> this related information. Flymake does use tooltips to display th error
> message, but those seem to be only able to display when the mouse is over
> the text, unless I'm missing something.
This is a globally useful feature. You might like to take a look at
help-at-pt.el. Notice that the feature you're trying to implement does
not require hooking into the point-motion itself (like
point-enter/point-leave/intangible properties) but only into the cursor
movement (i.e. the position of point betwen commands). This is an
important difference, since one is implemented at a very low level and
affects all kinds of unrelated operations, whereas the other is
implemented at a very high level and interacts with very little
other code.
Stefan