You can write a short, one-time sub to do it: 
#!/usr/bin/perl -w

use strict;

use vars qw(%bar);

$bar{foo} = sub { print "hello\n"};

callif($bar{foo});
callif($bar{quux});


sub callif
{
  my $var = shift;
  $var->(@_)
      if($var);
}

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In reply to Re: Shortening "$bar{foo} if exists $bar{foo}"? by sgifford
in thread Shortening "$bar{foo} if exists $bar{foo}"? by BUU

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