Regards,

Roman

2010/4/30 Harald Hanche-Olsen <hanche@math.ntnu.no>

It seems to me that the hyperspec is quite specific about

(expt 0.0 0):

When power-number is an integer 0, then the result is always the

value one in the type of base-number, even if the base-number is

zero (of any type). That is:

(expt x 0) == (coerce 1 (type-of x))

You can't possibly get any clearer than that.

And it continues:

If power-number is a zero of any other type, then the result is also

the value one, in the type of the arguments after the application of

the contagion rules in Section 12.1.1.2 (Contagion in Numeric

Operations), with one exception: the consequences are undefined if

base-number is zero when power-number is zero and not of type

integer.

In other words, the consequences of (expt ZERO 0.0) are undefined if

ZERO is a zero of any type.

- Harald

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