Brethren,

Here on perlmonks, I've picked up the nifty way of initializing a hash 

 @foo{1,2,3} = qw(a b c);

[download]
works the same as 
%foo = (
   1 => 'a'
   2 => 'b'
   3 => 'c')

[download]
which has been very handy to me several times when I've had a pair of 'parallel' lists that I wanted to turn into a hash. 
@foo{@keys} = @values;
# instead of
$foo{$_} = shift(@values) foreach @keys

[download]
But I don't understand why it works. I mean, @foo, %foo and $foo are three separate data-structures. @foo{@keys} = @values; looks like it's affecting @foo. But it isn't. It's affecting %foo.

Howscome?

I have an intuition that this has to do with (de)referencing of typeglobs, but I don't have nearly enough enlightenment. So I can copy the recipe by rote, but have insufficient insight into the Perl-nature of *foo.

throop

In reply to Hash initialization works, but why? by throop

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