C:\Users\Administrator>perl -E"my @bb = 1..10; for(keys @bb[1..5]){say;}
Experimental keys on scalar is now forbidden at -e line 1.
Type of arg 1 to keys must be hash or array (not array slice) at -e line 1, near "])"
Execution of -e aborted due to compilation errors.

C:\Users\Administrator>perl -E"my @bb = 1..10; @cc = @bb[1..5]; for(keys @cc){say;}
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