Re^3: [Perl 6] Any provision for a "dereferencing object"?

in reply to Re^2: [Perl 6] Any provision for a "dereferencing object"?
in thread [Perl 6] Any provision for a "dereferencing object"?

multi sub infix:<at> ($dsc, Code $deref) {
  $deref($dsc);
}

my %data = ( foo => [ { quux => 3 }, { bar => { baz => [ 1, 2, 3, 4 ] 
+}, }, ], );

my $dereferencer = { .<foo>[1]<bar><baz>[3] };

say %data at $dereferencer;
[download]

Works in Pugs. Since there doesn't seem to be any good documentation about macros yet, I don't know how to beautify the dereferencer construction syntax, but it ought to be trivial to make a macro that translates deref <foo><bar><baz>[1] to { .<foo><bar><baz>[1] }.

UPDATE: Fixed some blaring typos in the code. Thanks for noting it, blazar. (For some reason, you can't define a Hash in Pugs with

my Hash %foo = (
# something
);
[download]

At least I get a syntax error with Pugs 6.2.13.)

--
print "Just Another Perl Adept\n";

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Re^4: [Perl 6] Any provision for a "dereferencing object"? by blazar (Canon) on May 29, 2007 at 11:53 UTC
`$dereferencer = { .<foo>[1]<bar><baz>[3] };` [download] I knew that "unary" dot acts implicitly on `$_`, but appearently your code implies that in code written as a bare block `$_` is an alias to the first positional argument, and that I didn't know. Actually, without knowing, I would have written the above amongst other possibilities, like: `$dereferencer = -> $d { $d.<foo>[1]<bar><baz>[3] };` [download]	[reply] [d/l] [select]

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Re^4: [Perl 6] Any provision for a "dereferencing object"?
by blazar (Canon) on May 29, 2007 at 11:53 UTC

$dereferencer = { .<foo>[1]<bar><baz>[3] };
[download]

I knew that "unary" dot acts implicitly on $_, but appearently your code implies that in code written as a bare block $_ is an alias to the first positional argument, and that I didn't know. Actually, without knowing, I would have written the above amongst other possibilities, like:

$dereferencer = -> $d { $d.<foo>[1]<bar><baz>[3] };
[download]

[reply]
[d/l]
[select]

In Section Meditations