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Postings from May 2001
On Fri, May 18, 2001 at 01:34:55PM -0700, Nathan Wiger wrote:
> Dammit, I got the example exactly backwards. Try this:
>> $Foo is true;
>> $Foo = 0;
>> print "Stuff" if $Foo; # *WOULD* print - "is" assigns a
>> # permanent "true" property
Sorry to jump out of lurk-mode like this, it's just that I'm trying real
hard to understand how this can be useful..
While I understand how "0 but true" is a cute hack that is destined to
be replaced by a truth property, I fail to realize how it's useful to
have a value that's true no matter what value you assign to it later.
In the case of "0 but true", you return failure with undef, but if a
function doesn't signal failure in any way - testing its return-value
isn't going to be very helpful. So, what I'm struggling the most with is
how it's useful to actually test the truth of a variable that is
guaranteed to be true.
To me, this looks almost like an if-test like this:
foreach my $key (keys %hash) {
next unless exists $hash{$key};
...
}
(ok, strictly speaking, that was an unless-test ;)
Anyway - I'm not sure how properties are supposed to work yet. Should
all properties behave in the same way, or can every propery completely
define its own behaviour?
I mean - if you can override the "truth"-property by assigning to the
variable, why shouldn't one be able to override the "constant"-property
by assigning a new value to the constant?
--
// Trond Michelsen
\X/ mike@crusaders.no
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