On Wed, Apr 21, 2004 at 11:04:56AM -0400, Simon Glover wrote:
: Why? I was under the impression that in Perl 6 it was going to be
: possible to declare arrays that only contain values of a particular
: type -- I believe the syntax I saw was:
:
: my @array is float;
Just for the record, that's
my num @array;
You don't use "is" on any array unless you want to change the indexing
policy (think "tie" in Perl 5). The standard "is Array" type knows
how to deal with compactly stored low-level types as well as PMCs.
The type you declare out front is the return type of a single array
or hash element. The type you apply with "is" is the type of the
array or hash as an aggregate. Most aggregate types are parameterized
types based on the return type, if you think about it.
In any event, it is absolutely my intent that the builtin array
types of Perl 6 support PDL directly, both in terms of efficiency
and flexibility. You ain't seen Apocalypse 9 yet, but that's what
it's all about. Straight from my rfc list file:
ch09/116 Efficient numerics with perl
ch09/117.rr Perl syntax support for ranges
ch09/122 types and structures
ch09/123 Builtin: lazy
ch09/124 Sort order for any hash
ch09/136 Implementation of hash iterators
ch09/142 Enhanced Pack/Unpack
ch09/169.rr Proposed syntax for matrix element access and slicing.
ch09/202 Arrays: Overview of multidimensional array RFCs (RFC 203 through RFC
207)
ch09/203 Arrays: Notation for declaring and creating arrays
ch09/204 Arrays: Use list reference for multidimensional array access
ch09/205 Arrays: New operator ';' for creating array slices
ch09/206 Arrays: @#arr for getting the dimensions of an array
ch09/207 Arrays: Efficient Array Loops
ch09/225 Data: Superpositions
ch09/231 Data: Multi-dimensional arrays/hashes and slices
ch09/247 pack/unpack C-like enhancements
ch09/266 Any scalar can be a hash key
ch09/268.rr Keyed arrays
ch09/273 Internal representation of Pseudo-hashes using attributes.
ch09/282 Open-ended slices
ch09/341 unified container theory
Larry
