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Executive Summary: how can I get a source filter applied to required or evalled source code?

This came up while investigating some more features of load, when I suddenly realised that source filters have problems with AUTOLOADer modules, such as AutoLoader and SelfLoader (and of course load.pm). The problem basically is that they're not applied to require'd or eval'ed source. For example, take this module which basically uppercases any strings between double quotes:

# Foo.pm
package Foo;
use Filter::Util::Call ();
1;

sub import {
    Filter::Util::Call::filter_add( sub {
        my $status;
        if (($status = Filter::Util::Call::filter_read()) > 0) {
            s#("[^"]+")#\U$1\E#g;
        }
        $status;
    } );
} #import
[download]

This module is called in a script called "bar":

# bar
use Foo;

print "Hello World",$/;

#require 'bar2';  # source is not filtered  ;-(

{
 local $/;
 open my $handle,'<','bar2' or die $!;
 $source = <$handle>;
}
#eval $source;  # source is not filtered  ;-(
eval 'use Foo;'.$source;  # even with importing again, source is not f
+iltered  ;-(
[download]

and the external file "bar2":

# bar2
print "Just Another Perl Hacker",$/;
[download]

and alas, the output is always:

HELLO WORLD
Just Another Perl Hacker

whereas you would hope and/or expect:

HELLO WORLD
JUST ANOTHER PERL HACKER

These nodes seem related to this subject, but refer to other aspects of this problem I think.

I've been thinking a lot about this, but I guess I'm missing the right inspiration. I hope someone in the Monastery will have the right inspiration to fix this problem so I can add more features to load.pm.

Liz

In reply to Source filters in eval/require by liz

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