One could go the other way and allow user-defined code to act as push etc. do now.

Prototypes can do exactly that.
From perlsub: 
sub mypush (\@@)

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[TINPC@perlcabal.com shh]$ su real

In reply to Re: Consistency, syntax, and little minds by Felonious
in thread Consistency, syntax, and little minds by belg4mit

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