my %actions = (
       this => \&this,
       that => \&that,
       foo  => \&foo,
       bar  => \&bar,
       zzz  => \&sleepytime);

##</code><code>##

if($in eq "this"){&this}
if($in eq "that"){&that}
if($in eq "foo"){&foo}
if($in eq "bar"){&bar}
if($in eq "zzz"){&zzz}

##</code><code>##

foreach(@actions){ if($in eq $_){&$_()}}

##</code><code>##

$in=param('in');
@actions=qw(this that foo bar zzz); 
foreach(@actions){ no strict "refs"; if($in eq $_){&$_()}}