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Date: Tue, 21 Sep 2021 00:24:43 -0700 (PDT)
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Subject: Re: Exception Handling within Gtkada
From: Emmanuel Briot <briot.emmanuel@gmail.com>
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Xref: reader02.eternal-september.org comp.lang.ada:62805
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> > Generally, Ada exceptions must not left scope of callback function. Thu=
s, such code should be added to each callback/event handler/etc. subprogram=
 of your application.
> Right. Each handler should end like this:=20

We were talking the other day of the high-level Connect subprograms generat=
ed by GtkAda (`Gtk.Button.On_Clicked` and so on). Those will always catch e=
xceptions and avoid propagating them to the C layer in gtk+ (which as Dmitr=
y mentions is dangerous). They will in effect call `GtkAda.Bindings.Process=
_Exception`, which in turns calls a user-defined subprogram, see GtkAda.Bin=
dings.Set_On_Exceptions

I think this should be the recommended approach for general exceptions. Of =
course, your callbacks should directly handle exceptions that they know how=
 to recover from, and deal with that locally.