From @masak

<jaffa4> I How can I make a reference to scalar?
<masak> m​: my $scalar = 42; my $ref = \$scalar; $scalar++; say $ref
<camelia> rakudo-moar 367b58​: OUTPUT«\(43)␤»
<jaffa4> masak​: is it not that capture?
<masak> jaffa4​: yes, that is a capture. when someone asks about
"taking a reference" in Perl 6, I think about captures.
<jaffa4> masak : there is a problem with that reference... cannot
change variable value
<jnthn> A Capture can be indexed positionally to get the things in it
<jnthn> m​: my $a = 41; my $b = \($a); $b[0]++; say $a
<camelia> rakudo-moar 367b58​: OUTPUT«Cannot assign to an immutable value [...]
<jnthn> ah
<jnthn> But yeah, the usual way to do such things these days is "is
rw" parameters and so on
<Ben_Goldberg> m​: my $scalar = 42; my $ref = \$scalar; { ++$_ }( |$ref
); say $scalar;
<camelia> rakudo-moar 367b58​: OUTPUT«43␤»
<jaffa4> jnthn​: so is it a bug?
<jnthn> That you can't ++ the [0]'d thing maybe is
* masak submits rakudobug
<jnthn> masak​: Thanks, I'm just a bit too tired to fix that now, but
can easily do it in the morning :)

From @jnthn

On Sun Jun 28 13​:33​:09 2015, masak wrote​:

<jaffa4> I How can I make a reference to scalar?
<masak> m​: my $scalar = 42; my $ref = \$scalar; $scalar++; say $ref
<camelia> rakudo-moar 367b58​: OUTPUT«\(43)␤»
<jaffa4> masak​: is it not that capture?
<masak> jaffa4​: yes, that is a capture. when someone asks about
"taking a reference" in Perl 6, I think about captures.
<jaffa4> masak : there is a problem with that reference... cannot
change variable value
<jnthn> A Capture can be indexed positionally to get the things in it
<jnthn> m​: my $a = 41; my $b = \($a); $b[0]++; say $a
<camelia> rakudo-moar 367b58​: OUTPUT«Cannot assign to an immutable
value [...]
<jnthn> ah
<jnthn> But yeah, the usual way to do such things these days is "is
rw" parameters and so on
<Ben_Goldberg> m​: my $scalar = 42; my $ref = \$scalar; { ++$_ }( |$ref
); say $scalar;
<camelia> rakudo-moar 367b58​: OUTPUT«43␤»
<jaffa4> jnthn​: so is it a bug?
<jnthn> That you can't ++ the [0]'d thing maybe is
* masak submits rakudobug
<jnthn> masak​: Thanks, I'm just a bit too tired to fix that now, but
can easily do it in the morning :)

Fixed, and tests added to S02-types/capture.t.

The RT System itself - Status changed from 'new' to 'open'

@jnthn - Status changed from 'open' to 'resolved'