On map

[Bryan R Harris]

I have a curiosity maybe someone here can help with.

This code:

   @a=(1,2);
   map { $_ = 3 } @a;
   print join(",", @a), "\n";

... prints "3,3".  That map is changing the @a array as it goes through it.
Good.

Now this:

   %a=(1,2);
   map { $_ = 3 } keys %a;
   print join(",", keys(%a)), "\n";

I expected this to print "3", but it doesn't -- it prints "1".  If map sets
$_ as an alias to the value, why isn't it changing the keys?

Thanks!

- Bryan



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