clipka <ano### [at] anonymousorg> wrote:

I take it that's an implied confirmation that select() evaluates all the return
arguments before returning the conditional result.

> Are you sure that N-V=0, too?

"Yes."   #for (V, 0, N)....
So N-V when V=N _should_ indeed "equal zero"
But I'm in the middle of debugging the chain-linked macros I've coded, so I
shall find out for certain.
Right now, I'm making them more svelt.  More chain-link, less barbed-wire.

> In a macro? Why, yes, of course! Why not use `#if` instead of `select`?

Because that seemed iffy?  :P

I like to branch out and sample the different methods of doing things, and keep
my function {} skills unatrophied.   :P

Because sometimes I just don't like the if-[then]-else-end block and select()
seemed visually neater.   And every little thing that's not distracting helps.



> > Isn't there a pow function that tolerates / passes through pow(0,0) as 0, like
> > the magical atan2 ?
>
> And what result should that function return?

Bags of hundred dollar bills.


Oh, how I could have bet money that this question would be asked...   :D

> In some applications, you may want the result to be 1, to conform with
> x^0=1;

pow1 (x, 0) = 1

> in other applications, a result of 0 would make more sense, to
> conform with 0^x=0.

pow0 (x,0) = 1

> And in yet other applications, the most sensible thing to do is catch
> this case further upstream and report that something's just totally wrong.

pow (x, 0) = undefined, out of range, error, nil, nul, whatever you'd like.
Maybe just make it a warning.

roll it up to include all three:

pow (x, 0, Mode)

Something.  I just think that 25-year-old legendary software ought to be mature
enough to not require the user to code their way out of something that should
only require a switch or the trivial documented use of an alternate function -
like with atan() and atan2().

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