http://perldoc.perl.org/functions/exists.html 


use strict;
use warnings;


if (exists &FOO::bar)
{
        print "bar exists in foo\n";
}

package FOO;

sub bar
{
}

[download]
Update: tirwhan has raised an important distinction. This method will only tell you if the package contains a sub with that name. If the package inherits a sub with that name, it won't return true. So the choice depends on whether your logic requires 'package has subroutine named x' or 'package can do x'.

--------------------------------------------------------------

"If there is such a phenomenon as absolute evil, it consists in treating another human being as a thing."

John Brunner, "The Shockwave Rider".

In reply to Re: How to tell methods exist in a package by g0n
in thread How to tell methods exist in a package by jeanluca

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