Re: pl/perl problem

FERREIRA William (COFRAMI) wrote:
> my function is very long but i found an example with the same comportment :
> CREATE OR REPLACE FUNCTION adoc.totoTest()
> RETURNS int4 AS
> $BODY$
> my $var = '->>>';
> &concat($var);
>
> sub concat {
> $var .= 'tagada';
> }
> elog NOTICE, $var;
> return 4;
>
> $BODY$
> LANGUAGE 'plperl' VOLATILE;
>
> first execution : ->>>tagada
> second execution : ->>>

In the example above $var in sub concat is NOT an argument provided to
the function. What you've done there is create a named closure (if I'm
getting my terms right) in which the inner $var is allocated on first
call but not afterwards. The second time you run totoTest() the outer
$var (my $var) is a new variable, whereas the inner one still refers to
the original.

If you actually want to return a concatenated string you'd want
something like:

sub concat {
my $var = shift;
return $var . 'tagada';
}

If you want to affect an outer variable you'll want something like

sub concat {
my $var_ref = shift;
$$var_ref .= 'tagada';
}

Does that help?
--
Richard Huxton
Archonet Ltd