From the Perl/Tk Pocket Reference:

Binding callbacks can be nested using the Ev(...) constructor. Ev(...) inserts callback objects into the argument list. When Perl/Tk prepares the argument list for the callback it is about to call it spots these special objects and recursively applies the callback process to them.

Be well,
rir

In reply to Re: I don't understand a piece of Perl/Tk code by rir
in thread I don't understand a piece of Perl/Tk code by spx2

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