Stéphane Payrard wrote:
[snip]
> Non alphabetic characters are very conspicuous, so redundancy should
> be avoided. But Sigil _and_square/curly bracket are redundant.
Not quite...
In Perl5, the dereference operator (->) is optional between pairs of
subscript operators, so $foo[$x]->[$y] can be written as $foo[$x][$y],
but the first -> isn't optional... you cannot write $bar->[$x] as
$bar[$x], since that would be an access to @bar, not $bar.
In Perl6, since array accesses are always written as @a[$b], never as
$a[$b], it's possible to write $a.[$b] (array dereference) as $a[$b],
which is rather nicer looking, imho.
Thus, in Perl6, @a[$b] is an access to the array @a, and $a[$b] is an
access to the arrayref $a.
> Space as syntax can be a device to drop the sigil when dereferncing an
> array or a hash.
>
> a [$a] # call the function 'a' with a
> # reference to an array as parameter
> a[$a] # dereference the array @a
But '@a' isn't a reference... did you mean 'index into' instead of
dereference?
Also, part of the goal of perl6 is to simplify the grammer, make it more
consistant -- this would make accesses to arrays different from accesses
to arrayreferences.
I prefer for whitespace to be mostly meaningless -- this isn't python.
> Same thing goes for C<a {$a}> and C<a{$a}>.
>
> Certainly, within double quotes one has to write C<@a[$a]> because
> without the sigil, that would be to easy to accidentally dereference
> an array. This is a case of preferring convenience over
> consistency. Probably for the consistency freaks C<a[$a]> should be
> allowed as well as C<@a[$a]> outside double quoting context.
Allowing two different ways of writting an array access is
*in*consistant, and the one which looks like a function call instead of
an array access, and which makes the grammer more complicated -- that
is, your proposed a[$a] -- should be dropped from the language.
(Perl5 allows two different ways of writing arrayref accesses, one being
$$a[$b], the other being $a->[$b]. This is inconsistant, and I would
love it if we could drop $$a[$b], but sadly, we need to be backwards
compatible, and also, the $a->[$b] syntax doesn't support slices.)
--
$a=24;split//,240513;s/\B/ => /for@@=qw(ac ab bc ba cb ca
);{push(@b,$a),($a-=6)^=1 for 2..$a/6x--$|;print "[EMAIL PROTECTED]
]\n";((6<=($a-=6))?$a+=$_[$a%6]-$a%6:($a=pop @b))&&redo;}
