Re: perlsub

On Sat, 2003-10-04 at 00:29, Nabil Sayegh wrote:
> Hello again,
>
> now that perlsub works i need to know how backreferences work with
> plperl. $1 - $9 doesn't work. Any idea ?
>
> perlsub:
> -----------------------------------------------
> CREATE FUNCTION perlsub(text, text, text) RETURNS text AS '
> my ($data, $pat, $repl) = @_;
> $data =~ s/$pat/$repl/;
> return $data
> ' LANGUAGE 'plperl';
> -----------------------------------------------
>
> SELECT perlsub('a=b','([^=]+)=(.+)','key:$1;val:$2');
>
> Any idea ? Just a matter of quoting ?

It's a problem with Perl itself rather than with PL/Perl. I tried that
in a Perl script and it produces the same result. I couldn't find any
way of including $ in the replacement string as a metacharacter.

You need to consult a Perl guru.

When you do get an example that works in a script, remember to double
any single quotes and backslashes when you create the function.

> Also this example doesn't work with * instead of + :(

I don't see any difference:

junk=# SELECT perlsub('a=b','([^=]*)=(.*)','key:$1;val:$2');
perlsub
---------------
key:$1;val:$2
(1 row)

junk=# SELECT perlsub('a=b','([^=]+)=(.+)','key:$1;val:$2');
perlsub
---------------
key:$1;val:$2
(1 row)

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