is my test doing a reasonable job of timing?

Nothing pops out at me.

Is scalar(@array) is slower because it requires a function call?

That would be my guess, yes. It has to build the entire @_ variable from your huge array input. That alone is going to slow it down.

But at the level of almost 2 million per second in the slowest case, I really wouldn't worry about it (:

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated