Interestingly, that's the solution I came up with last night.

sub import {
    # two loops because we don't want to splice @_ while looping over 
+it
    if ( grep { /:(?:bar|baz)/ } @_ ) {
        my $sub = caller(0) . '::set';
        {
            no strict 'refs';
            *{$sub} = \&set;
        }
    }
    # using goto to avoid updating caller
    goto &Foo::import;
}

[download]

I wound up providing a &set function for the globals, but needed to make it available as both a method and a function. When a person calls my constructor, they get the new method. If they want to use the methods as functions, I install the method in their namespace and then use goto to call the &import method of the base class.

For those who don't understand that last bit, goto with a sub after it replaces the current subroutine called with the subroutine that you're calling. This has the effect of not updating the call stack, thereby allowing the base class to export to the client, instead of my class.

Cheers,
Ovid

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In reply to (Ovid) Re: Re (tilly) 3: Setting Globals in a Base Class by Ovid
in thread Setting Globals in a Base Class by Ovid

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