If $new and $old are hashrefs, then you can still do the slice as follows: 
@$old{keys %$new} = values %$new;

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Just remember that the $ is part of the name of the hash, and it should make sense. :-)

In reply to Re (tilly) 1: Slicing a hashref by tilly
in thread Slicing a hashref by George_Sherston

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