never knew that the l-valueness of a subroutine was allied to its prototype

It's not. &vec calls vec of the package in which you happen to be, not the core function. 

>perl -e"&vec()"
Undefined subroutine &main::vec called at -e line 1.

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The (presumably non-existant) vec in your current package is not an l-value sub, thus the error messag. You can't use & on core functions.

In reply to Re^7: What would you change? by ikegami
in thread What would you change? by BrowserUk

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