The value of key1 has to be laying around somewhere?!?

No, but you can bookmark it if you want: 

my %hash = map {
                  my $foo;
                  $_ => {
                          key1 => $foo = 'longstring'.$_.'more',
                          key2 => alter( $foo ),
                        }
               } @list;

[download]

That would work, though I am not sure I would recommend it. A two-stage approach would/might be cleaner, I think: 

my %hash = map {
                  my $foo = { key1 => 'longstring'.$_.'more' };
                  $foo->{"key2"} = alter( $foo->{"key1"} );
                  $_ => $foo;  
               } @list;

[download]

Actually, now that I've written both, I can't decide which is cleaner.

In reply to Re: Is it possible to use key/values of a Hash/Hash ref while it's being initialized? by fishbot_v2
in thread Is it possible to use key/values of a Hash/Hash ref while it's being initialized? by shiza

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