On Wed, Jul 16, 2008 at 10:04:03AM -0700, Larry Wall wrote: > On Sun, Jul 13, 2008 at 02:17:10PM -0500, Adrian Kreher wrote: > : Hi, > : > : I'm reviewing the tests in S09, and the file > : t/spec/S02-builtin_data_types/multi_dimensional_array.t uses the [0][0] > : indexing format interchangeably with [0;0]. > : > : These two formats mean two different things, correct? The [0][0] form isn't > : mentioned much in the spec, nor is [0;0] or if they interact somehow. > > I think they should come out to meaning the same thing, though the > [0][0] form may be less efficient if it has to temporarily construct > a slice of the next dimension of the array. On the other hand, a > naïve implementation of the multidimensional subscripter might just do > the same thing internally for the semicolon, so it could be a wash.
Would it be counter-productive to specify that the implementation is allowed to compile time optimise [$a][$b] etc to [$a;$b] etc? I'm assuming that it is allowed for the implementation of a multidmentional array to have different semantics for [$a][$b] and [$a;$b], but that seems to violate good sense, much like overloading a class in Perl 5 (or any other language) such that (++$a) and ($a + 1) are not the same. Nicholas Clark
