Hello !

I recently began to play with Perl exception mechanisms, and gave a try to the Error module with the "try/catch" syntax.
However, reading docs ( Matt Sergeant presentation), I discovered that it presents a serious issue with regard to closures, and creates memory leaks.
But I also read in the DDJ article from Dave Rolsky that Perl >= 5.8.4 might fix the closure issue ?
Trying the test sample provided in the presentation:

#!/usr/bin/perl -w
use strict;
use warnings;

use Error qw(:try);
for (1..3) {
    my $x = Foo->new();
    try {
        try { print "$_: $x\n" };
    };
}
END { warn("interpreter exit\n") }
package Foo;
sub new { return bless {}, shift }
sub DESTROY { warn("Foo::DESTROY\n") }
[download]

I indeed notice that the output result changes between perl 5.6.1:

1: Foo=HASH(0x80f6084)
2: Foo=HASH(0x813b750)
3: Foo=HASH(0x815a0f0)
interpreter exit
Foo::DESTROY
Foo::DESTROY
Foo::DESTROY
[download]

and Perl 5.10.0:

1: Foo=HASH(0x81981f8)
Foo::DESTROY
2: Foo=HASH(0x81981f8)
Foo::DESTROY
3: Foo=HASH(0x81981f8)
Foo::DESTROY
interpreter exit
[download]

The object seems indeed destroyed when leaving the loop's scope.

Can we then consider that this closure issue when using the "try/catch" syntax of the Error package is over ? Is it now advisable to use the Error module with the "try/catch" syntax ?

Nothing appears indeed in the perl584delta.pod about closures.

Regards,
Pierre

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