Re: [HACKERS] pl/perl thoughts

[Andrew Dunstan]

FWIW, I have now tested the scheme below, and it appears to work as 
expected. I can't see any reason it should disturb any existing 
functionality, unless people currently use plperl to store nonlexical 
variables which might now clobber each other. I think it's worth doing, 
for a small but nontrivial functionality gain. If nobody objects, I will 
submit a patch and some docco on how to use it.

cheers

andrew

I wrote:

Thus the following perl contained in plperl.c and executed on 
interpreter startup:

               require Safe; SPI::bootstrap();
               sub ::mksafefunc { my $x = new Safe; 
$x->permit_only(':default');$x->permit(':base_math');
               $x->share(qw[&elog &DEBUG &LOG &INFO &NOTICE &WARNING 
&ERROR]);
                return $x->reval(qq[sub { $_[0] }]); }
               sub ::mkunsafefunc {return eval(qq[ sub { $_[0] } ]); }

would become something like:

               require Safe; SPI::bootstrap();
               use vars qw($PLContainer); $PLContainer = new 
Safe("PLPerl");
               
$PLContainer->permit_only(':default');$PLContainer->permit(':base_math'); 

               $PLContainer->share(qw[&elog &DEBUG &LOG &INFO &NOTICE 
&WARNING &ERROR]);
               sub ::mksafefunc { return $PLContainer->reval(qq[sub { 
$_[0] }]); }
               sub ::mkunsafefunc {return eval(qq[ sub { $_[0] } ]); }

Now you could do something like this:

create function myplperlfuncs() returns int language plperl as '
   $datavar = "foo";
   $funcvar = sub { return "bar"; };
   return 1;
';
create function f1 () returns text language plperl as '
 return $datavar;
';
create function f2() returns text language plperl as '
 return &$funcvar();
';
At the start of your session you would issue "select 
myplperlfuncs();" to preload the values, and thereafter you could 
call f1() and f2() quite happily.




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