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)
 

-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight, UK                             http://www.lfix.co.uk/oliver
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