in reply to See if a certain package has a certain sub, without executing that sub
Use the can method (it's a method of the UNIVERSAL package, so every class in Perl has access to it).
#!/usr/bin/perl use strict; use warnings; package Communications; sub SendMessage { my $packages = shift; my $msg = shift; for (@$packages) { if ($_->can('ReceiveMessage') ) { $_->ReceiveMessage($msg); } else { print "$_ can't ReceiveMessage\n" } } } sub ReceiveMessage { print __PACKAGE__, "::ReceiveMessage('$_[1]')\n"; } package Second; sub ReceiveMessage { print __PACKAGE__, "::ReceiveMessage('$_[1]')\n"; } package Other; sub nothing { print "\n"; } package main; my @packages = qw(Communications Other Second); Communications::SendMessage( \@packages, 'hello'); __END__ output: Communications::ReceiveMessage('hello') Other can't ReceiveMessage Second::ReceiveMessage('hello')
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Re: Re: See if a certain package has a certain sub, without executing that sub
by muba (Priest) on Mar 20, 2004 at 15:33 UTC |
In Section
Seekers of Perl Wisdom