@a is an array. The first element of @a is $a[0], which stores a reference to an array of three elements. You can extract the inner array using @{ $a[0] }. Unlike the other suggestions, this works for the (fictional) array stored in $a[1] or other positions, and it can be extended for the third-level, fourth-level, etc.

As Occam said: Entia non sunt multiplicanda praeter necessitatem.

In reply to Re: size of an array ref by TomDLux
in thread size of an array ref by fionbarr

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