Hi,
my ($a, $b, $c) = <a b c>;
my $also_a := ($a,$b,$c)[0];
$also_a eq "a"; # correct?
$also_a = "A"; # does not die?
$a eq "A"; # true?
my $also_b = "b";
($a,$b,$c)[1] := $also_b;
$b eq "b"; # true?
$b = "B"; # does not die?
$also_b eq "B"; # true?
Note that if my assumptions are correct, the following expressions must
be true as well (also see [1]), unless there's some additional magic.
($a,$b,$c)[0] =:= $a;
($a,$b,$c)[1] =:= $b;
($a,$b,$c)[2] =:= $c;
Thus:
($a,$b,$c)[1] = 42; # same as $b = 42
And:
(0,1,2)[1] = 42; # dies ("cannot modify constant")
(0,1,2)[1] := 42; # dies ("cannot rebind constant")
my @foo = <a b c>;
my @bar = <d e f>;
(@foo,@bar)[2] =:= @foo[2]; # true
(@foo,@bar)[3] =:= @bar[0]; # true
(@foo,@bar)[2] = 42; # same as @foo[2] = 42
(@foo,@bar)[3] = 42; # same as @bar[0] = 42
(@foo,@bar)[2] := 42; # same as @foo[2] := 42
(@foo,@bar)[3] := 42; # same as @bar[0] := 42
(These questions were motivated by Flavio's work in progress [2] ("A
draft on the runtime view of how Lazy things (like Arrays) work").)
--Ingo
[1] http://www.nntp.perl.org/group/perl.perl6.language/22924
[2] http://svn.openfoundry.org/pugs/docs/notes/laziness.txt
