my $r = { subref => sub { return 2 * $_[0] } };

my $tied;

tie $tied, 'TieTest', $r; 

# This will perform the pre-action before executing
print $tied->(5);

# These will not
for(0..100){

    print $tied->(5), "\n";
}

package TieTest;

sub TIESCALAR{
    
    my $caller = shift;
    my $r      = shift;
    
    bless $r, $caller;
}

sub FETCH{
    
    my $r = shift;
    
    print "Checking for pause...\n";
    
    return $$r{subref};
}

##</code><code>##


# This will perform the pre-action before executing
print $tied;

# These will not
for(0..10){

    print $tied, "\n";
}