I couldn't turn up any great links on the subject, but Objective-C (as used in Apple's Cocoa development) uses this pattern. Calling a method on a nil object returns nil. It'd be similar to this Perl, which would print undefined: 
# this would work if it were Objective-C
# using Perl's syntax
my $foo    = undef;
my $result = $foo->message;
print "undefined\n"
    if not defined $result;

[download]
I happen to like it.

elusion : http://matt.diephouse.com

In reply to Re: The Null Mull (or, when OO needs more O) by elusion
in thread The Null Mull (or, when OO needs more O) by brian_d_foy

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