[m-rev.] for review: do not allow std_util.pow/3 with negative values

[Peter Wang]

On Wed, 11 Jan 2023 16:03:54 +1100 Julien Fischer <jfischer at opturion.com> wrote:
> 
> For review by anyone.
> 
> ----------------------
> 
> Do not allow std_util.pow/3 with negative values.
> 
> library/std_util.m:
>      Make std_util.pow/3 throw an exception if it is called with a negative
>      integer as its second argument.
> 
> tests/hard_coded/Mmakefile:
> tests/hard_coded/func_exp.{m,exp}:
>      Add a test of pow/3.
> 
> NEWS:
>      Announce the above change.

That's fine.

Has pow ever been useful?

Peter