I stumbled upon this while checking docs. Nette\Callback is deprecated and
AFAIK Kdyby is not leveraging much benefits from it.
This question was answered by Filip Procházka,
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Can you elaborate more? Why should I not use it?
It is deprecated in Nette and Kdyby uses them only as containers. I look at
them now as on unnecessary wrapping of callback. It would make sense if Kdyby
depended on thrown exception for invalid callbacks etc.
I guess we can do that. If you wanna help, either send pullrequests or at
least open issues on repos that use the callback object. Thanks!