sub link {
    my ($repl,$obj) = @_;
    if (! $repl->{linkedVars}) {
        $repl->{linkedVars} = {};
        $repl->{linkedIdNext} = 1;
    };
    
    if (defined $obj) {
        $repl->{linkedVars}->{ $repl->{linkedIdNext} } = obj;
        return $repl->{linkedIdNext}++;
    } else {
        return undef
    };
};