Re: How to check if a function reference is valid or not?

On Wed, Nov 28, 2007 at 02:15:39AM -0800, howa wrote:

sub abc {
print 'abc';
}

print "<", exists &abc, ">\n";
print "<", exists &abcee, ">\n";

my $f1 = \&abc;
my $f2 = \&abcee;

print $f1; # return CODE(0x..)
print $f2; # also return CODE(0x..)

print "<", defined &abc, ">\n";
print "<", defined &abcee, ">\n";

$f1->();
$f2->();

How do I know if $f2 is a valid function reference, without actual
calling it?

perldoc -f exists
perldoc -f defined

Note that a sub exists after taking a reference to it even though it
won't necessarily e defined.

--
Paul Johnson - paul@xxxxxxxx
http://www.pjcj.net
.

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