You could say: 
my $self;
$self = shift if (UNIVERSAL::isa( $_[0], 'My::Object' );

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I'd rather see a procedural interface that uses a default singleton object. Under the hood, it's using the OO interface, but the actual object is hidden from users, if that's necessary.

In reply to Re: Creating modules with OO and functional interfaces. by chromatic
in thread Creating modules with OO and functional interfaces. by BazB

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