Re: [9fans] float.h

[Pietro Gagliardi <pietro10@mac.com>]

On Aug 6, 2008, at 4:06 AM, Charles Forsyth wrote:

>> My  program uses some of them (DBL_MIN, DBL_MAX, DBL_EPSILON), and
>> including <ape/float.h> yields name clashes. Thanks.
>
>> #include <u.h>
>> ...
>> #include <ape/float.h>
>
> it's surprisingly important not to leave out important information,
> such as
> what important things were in the "..." (other include files) and,
> most importantly, the particular "name clashes".
>
> i'd noticed you were using <ape/float.h> not <float.h> which i'd
> thought curious
> (were you mixing APE and Plan 9 include files?) but like most others
> i'd initially
> assumed the "name clashes" had to do with the DBL_ names. odd.
>

Yes. Plan 9 has no float.h of its own.

> guessing that the "..." contained "#include <libc.h>" and trying a
> little test,
> I find that probably the "name clashes" were (was?) probably singular:
>
> /386/include/ape/float.h:43 yy.c:3 redeclare tag: FPdbleword
>

The other is in <u.h>.

> so now we know the problem, what to do about it?
> i know an unpleasant way but perhaps someone else can think of a
> good way to get those
> values outside the APE include files.  libc.h doesn't define
> equivalents.
> perhaps the values aren't actually all that useful (i'm not sure how
> i'd use
> them myself in a calculator, for instance).
>
>

If your unpleasant way is to copy float.h, it won't work; you'll need
one for each $objtype. I found an algorithm to get epsilon, but not
min or max.