132777 - Exception in event handler does not cancel the event (should it?)

Status: RESOLVED WONTFIX

(Core :: DOM: Events, defect, P5)

Description

[Vytautas]

Try this:
<a href="http://www.lrytas.lt" onclick="alert();return false;">aaaaa</a>
It is working.

Try this:
<a href="http://www.lrytas.lt" onclick="alert();return false;">aaaaa</a>
It doesn't work.

Comment 1

[Marc Boullet]

Any difference I'm missing between the two cases.

Comment 2

[Vytautas]

It should be:
Try this, one function:
<a href="http://www.lrytas.lt" onclick="return false;">aaaaa</a>
It is working.

Try this, two functions:
<a href="http://www.lrytas.lt" onclick="alert();return false;">aaaaa</a>
It doesn't work.

Comment 3

[José Jeria]

That is incorrect Javascript. 
You have no string as an argument to the alert.

Comment 4

[Boris Zbarsky [:bzbarsky]]

Yep.  That's the problem...  the alert() with no arguments throws an exception
and so the return false is never executed.  Over to events to decide whether an
exception in an event handler should affect event propagation in any way.

Comment 5

[Vladimir Ermakov]

If it should this is low priority because its up to the web developer to make
sure that there is NO exceptions when execting an event handler.

Comment 6

[Boris Zbarsky [:bzbarsky]]

jst, should exceptions in an event handler cancel the event?  My instinct is "no".

Comment 7

[Johnny Stenback (:jst)]

I'd say no too. If you want to cancel an event, don't throw exceptions, catch
them and do the right thing in stead.