On 2003-02-07 at 11:13:07, Austin Hastings wrote:
> --- Michael Lazzaro <[EMAIL PROTECTED]> wrote:
> > I'm trying, and failing, to accurately and definitively answer the
> > question "what's the difference between an array and a list in
> > Perl6?"
>
> How's this?
> ============
>
> A list is a literal (e.g., '(3, "Hello, world")') that can be used as
> the initializer for an array.
>
> [...] places in perl that require "an array" can be given a list. The
> exception is lvalues -- you can't say 3 = "Hello, world"; -- the
> left-hand side of an assignment operation requires an assignable
> thing, not a literal. So the difference between a list and an array
> is one of assignability.
Not really, though. A list can be an lvalue, provided it is a list
of lvalues:
($a, $b, $c) = 1,2,3;
Although this may reasonably be regarded as a special case; you
certainly can't pop a list:
(1,2,3).pop => error
But there's also the case of anonymous arrays, constructed through
reference via [ . . . ]. These are pop'able:
[1,2,3].pop => 3
But they certainly aren't lvalues:
[$a,$b,$c] = 1,2,3 => error
Unless some magic autoconversion happens.
--
Mark REED | CNN Internet Technology
1 CNN Center Rm SW0831G | [EMAIL PROTECTED]
Atlanta, GA 30348 USA | +1 404 827 4754
