#4840 ($realpart '((mexpt) 0 -1001)) = 0

[David Scherfgen]

Spotted by Claude, difficult to reproduce in user-level code, but anyways:

:lisp ($realpart '((mexpt) 0 -1001))
0

So it's saying that the real part of 1 / 0^1001 = 1 / 0 is zero.

[Stavros Macrakis]

Not a bug. Realpart (like most functions) requires a simplified argument.

[David Scherfgen]

This comes from a function named powers, which handles its zero-base corner cases deliberately. 0^negative -> 0 is the one zero-base corner it doesn't get "right" - but since it's unreachable with simplified expressions, probably not worth fixing.