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From: Thomas Witt (witt_at_[hidden])
Date: 2002-05-17 10:06:31

Hash: SHA1

On Friday 17 May 2002 16:30, Douglas Gregor wrote:
> Would something like this have helped as a note in operator()?
> "Calling the function call operator may invoke undefined behavior if no
> slots are connected to the signal, depending on the combiner used. The
> default combiner is well-defined for zero slots when the return type is
> void but is undefined when the return type is any other type (because there
> is no way to synthesize a return value)."

Yes, a lot.

> I think the design is correct, but maybe the default behavior is wrong. It
> might be easier for users if the default behavior handled having no slots
> more gracefully (e.g., by silently returning a default-constructed value).

I have thought about something like this. I dropped it because I felt the
return value problem is something the user should be aware of. Better he
should think about the question of what the default should be. I thinks this
is mostly a question of personal preference.


- --
Dipl.-Ing. Thomas Witt
Institut fuer Verkehrswesen, Eisenbahnbau und -betrieb, Universitaet Hannover
voice: +49(0) 511 762 - 4273, fax: +49(0) 511 762-3001
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