my %functions_hash = 
( '^Created by ' => sub { $_[0] =~ /^Created by (\w+)/; $_[0] = $1; },
'^date :' => sub ( $_[0] =~ /^data :(#HELP!!)/; $_[0] = $1
 );
...
if ( $data =~ /$key/ ) { 
    $value->( $data );
}