Re: Perl OO: switch package context.

ovid once wrote a module to do that: aliased.

Otherwise: it's possible to have Class be a constant, in your package, with value "My::Package::Class". that ought to work too. Well, in my tests, it does. :)

package My::Package;
use constant Class => __PACKAGE__ . '::Class';

print ref Class->new;  # prints "My::Package::Class"

{
    package My::Package::Class;
    sub new {
        return bless {}, shift;
    }
}
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Comment on Re: Perl OO: switch package context. Download Code

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Re^2: Perl OO: switch package context. by sorhed (Acolyte) on May 15, 2005 at 13:03 UTC
OK, that works indeed. But (oh, I know it is cruel) I need to do that at runtime, within eval context. So: `use aliased Foo::Bar::Object; print ref Object->new();` [download] works, so works this one: `use constant Object => 'Foo::Bar::Object'; print ref Object->new();` [download] But eval'ing this stuff does not: `eval 'use aliased Gemini::Model::Object;'; print ref Object->new();` [download] or: `eval qq[use constant Object => 'Foo::Bar::Object';]; print ref Object->new();` [download] What's wrong with that? :)	[reply] [d/l] [select]
Re^3: Perl OO: switch package context. by bart (Canon) on May 15, 2005 at 20:45 UTC
It's too late at runtime, the rest of the script already got compiled. So "Object" is taken as a bareword string literal, and nothing can change that. As a `constant` is nothing but a sub, you can use a similar sub that just returns the value of a scalar. You can always change the value for the scalar. `my $class = "Gemini::Model::Object"; sub Object () { return $class; } print ref Object->new();` [download] You can always still change the value of that scalar. But why the obfuscation? If you want to use a variable class, just say so. Perl lets you do that. `my $class = "Gemini::Model::Object"; print ref $class->new();` [download] Looks fine to me.	[reply] [d/l] [select]