Just for curisosity - you write:
shift is one of those keywords...
The "sub"-perldoc uses similar vague language:
Many built-in functions may be overridden
Finally, some built-ins (e.g. "exists" or "grep") can't be overridden
Is there a list somewhere of the built-ins that can and those that cannot be overridden or is "many" and "some" all that's documented?

In reply to Re^4: shift in list context buggy? by morgon
in thread shift in list context buggy? by LanX

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