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an endless discussion thread about what features to include.
-- Jarkko Hietaniemi
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undef vs. '' (Score:1)
i usually find clarity using undef vs ''. for instance, i'd write
$pg->owns( undef, 'gold' );instead of
$pg->owns( '', 'gold' );then again, if i wanted a more 'prologgy' syntax, i think i'd create a constant with an undefined value, like
sub X () {}## or use constant X => undef;
$pg->owns( X, 'gold' );
in fact, i think i like the Prolog-like syntax in my last example. that's probably what i'll find myself using.
hrmmm... what if X is an lvalue subroutine?
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Re:undef vs. '' (Score:2)
I think you'll be relatively happy with this. In the auto-generated rules, if an argument is encountered with a false value, such as the empty string or undef, it's ignored (sort of). This means that if you prefer undef, you'll be perfectly free to use it.
As for $pg->owns( X, 'gold' );, I like the syntax, but forcing a person to predefine all of those constants means that it will be harder for them to generate queries on the fly.
use constant Who => '';