You could use eval EXPR, but passing a sub reference is safer, clearer and easier. 

my $condition = sub { !-d $_[0] };
my $result = checkForDirectory($condition);

sub checkForDirectory
{
    my $condition = shift;
    
    ...
    
    if ($condition->($someDir))
    {
        doSomethingElse();
    }
}

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In reply to Re: Pass conditions to a subroutine by ikegami
in thread Pass conditions to a subroutine by PerlRob

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