Recipe 1.10: Using Objects as Classes

Last Updated: Sep 8, 2003 Status: Very Likely

Problem:  

You want to use an object as if it were a Class. For example, you want to use CAN or HAS on an object, even though they are technically class methods, not instance methods.

Solution:  

Just do it:

$obj.CAN;

Discussion:

An object is, by definition, nothing more than a specific instance of a builtin type or class. You may call class methods within an object just as you would call any other method: when the method is called, it will use the class of the object, and instance information will be unavailable.

In perl5, the first argument to a method was either a class name or an object instance, depending on how the method had been called. This led to code like:

sub foo {
    my $type = shift;
    $type = ref $type if ref $type;		# make sure it's a class name
    
    ...
}

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