@a[3,1] is an array slice, and an array slice is effectively the same as ($a[3], $a[1]), which is the comma operator.
and if the comma operator is called in scalar context it returns the last expression, $a[1].

In reply to Re: Confused as to why the "casting context" is mis-behaving by tinita
in thread Confused as to why the "casting context" is mis-behaving by kiz

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