I think you're misinterpreting the semantics and therefore the results.

If you call a subroutine in a scalar context, that context gets propogated to the expression that is calculating the return value automatically. Likewise, a list context. This is documented, and is not an "optimization", but a definition!

Remember, it's not just about list vs length of list... see my On Scalar Context for all the ways that this introduced context can affect the result.

Thus, a subroutine called in a scalar context could never have constructed any sort of list at any time during the return. It has to construct a scalar of the appropriate flavor. And for @foo, that's gonna be the length of the foo array, and none other.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: Optimizing with wantarray by merlyn
in thread Optimizing with wantarray by dragonchild

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