On Mon, May 16, 2005 at 12:49:13PM -0700, Larry Wall wrote: > On Tue, May 17, 2005 at 01:48:20AM +0800, Autrijus Tang wrote: > : This evaluates to 1 in Perl 5: > : > : not 4,3,2,1,0; > : > : Namely, the "not" listOp is taking the last of a variadic, non-slurpy > : argument list, boolify it, and return its negation. > : > : What is the Perl 6 signature that correspond to this behaviour? > > There is none. Wherever Perl 5 defaults to "last of list", Perl > 6 doesn't. If you wanted to emulate it in user code, you'd have "is > context(Scalar)" or some such and then explicitly ignore all but the > last value in your implementation. But no built-ins rely on C-comma > behavior.
Ok, but I'm still not too sure about what signature will Perl 6's ¬ have, that can impose singular context on each of its argument (so that not(@foo) won't flatten), but still accept an unlimited number of arguments. It's something like: multi sub not (Bool $x1) multi sub not (Bool $x1, Bool $x2) multi sub not (Bool $x1, Bool $x2, Bool $x3) ... But I'm not sure about how to express it in one line. > No. In list context it should do !俎4,3,2,1,0]. In scalar context it > should probably return something like !any(4,3,2,1,0) or none(4,3,2,1,0) > or whatever we decide makes our collective brain hurt the least. IMHO, having not($x, $y, $z) simply mean !(any($x, $y, $z)) is easiest to explain. Thanks, /Autrijus/
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