See How do I take a slice of a hash reference?, @{$self}{qw(uno dos tres}.

What would Perl6 do ?

$hashref<uno dos tres> = <some three values>;

(note that <...> is the replacement for qw(...) and for hash subscripts with literal strings).

Update: It's already implemented in Rakudo:

$ ./perl6 -e 'my $h = {}; $h<a b c> = 1..3; say $h.perl'
{"a" => 1, "b" => 2, "c" => 3}
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