I have a hash.. 

%hash=('A'=>1, 'B'=>2, 'C'=>3, 'D'=>4);

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..if I want to print this hash I have previously done:

@keyarr=(keys (%hash));
foreach (@keyarr)
{print hash{$_}=>$_;

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Now I have discovered that the following is possible:

foreach $key (sort (keys (%hash)))
{print "$key => $hash{$key}\n";}

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Could someone of you please explain what is happening here?
Is an array without name created that holds all the key values and each of the elements is called '$key'? It looks from the code like the $key variable is assigned all keyvalues at one time, this clearly can not be the case so what is going on?

Edited by planetscape - added code tags

In reply to Printing hash by tamaguchi

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