hashref slice syntax ?

NetWallah has asked for the wisdom of the Perl Monks concerning the following question:

Brethren - I found myself requiring :

  ($self->{ uno  },$self->{ dos }, $self->{ tres }) = qw|some three va
+lues|;
[download]

and thought - surely there is a better way, but could not figure out a functioning lazier syntax, either via a map, or variants of :

 # does not work
 @{$self->{qw|uno dos tres|}} = qw|some three values|;
[download]

Which would seem reasonable.

Is there such an animal as a hashref-slice ? as an LVALUE ?

If not, can this be done using map ? (LVALUE map ?)

What would Perl6 do ?

..to maintain is to slowly feel your soul, sanity and sentience ebb away as you become one with the Evil.

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Re: hashref slice syntax ? by wfsp (Abbot) on Feb 11, 2009 at 07:18 UTC
`@{$self}{qw{uno dos tres}} = qw{some three values};` [download] See tye's References quick reference.	[reply] [d/l]
Re: hashref slice syntax ? by moritz (Cardinal) on Feb 11, 2009 at 07:21 UTC
See How do I take a slice of a hash reference?, `@{$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}` [download]	[reply] [d/l] [select]
Re: hashref slice syntax ? by jwkrahn (Abbot) on Feb 11, 2009 at 07:19 UTC
Your hashref slice would be: `@{ $self }{ qw/uno dos tres/ } = qw\|some three values\|;` [download]	[reply] [d/l]
Re: hashref slice syntax ? by NetWallah (Canon) on Feb 11, 2009 at 22:22 UTC
Thanks for the enlightenment. Still curious though - can this be done using map ? i.e. can the result of a map be an LVALUE ? `(map {$self->{$_}} qw\|uno dos tres\|) = qw\|some three values\|; # Gives syntax error: # Can't modify map iterator in list assignment` [download] For perl6, I imagine I may use the zip operator `for zip(qw\|uno dos tres\|; qw\|some three values\|) -> $k, $v { $self->{$k} = $v; }` [download] as an alternative to moritz's simpler solution. ..to maintain is to slowly feel your soul, sanity and sentience ebb away as you become one with the Evil.	[reply] [d/l] [select]