Re: [PATCH] enable basic arithmetic with infinity

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Tue, Sep 23, 2014 at 05:03:41PM +0200, Jeroen Demeyer wrote:
> On 2014-09-23 16:03, Bill Allombert wrote:
> >Purposefully, we restricted the semantic attached to oo.
> >Most of the time such operations are the symptom of a bug.
> The usage quoted before [if (lambda > 2*valuation(x,p),...)] is not
> a bug, in fact it expresses something very natural and it would be a
> pity to force people to write
> 
> if (x!=0 && lambda > 2*valuation(x,p),...)

Maybe you will prefer the alternative:
my(v=valuation(x,p));
if (v!=oo && lambda > 2*v,...)

Personnally, I would never write 2*val(0) in a mathematical paper.

But your point that valuation should have returned an error from the
beginning is well-taken.

Cheers,
Bill.