Re: gnil

[Karim BELABAS <Karim.Belabas@math.u-psud.fr>]

On Tue, 10 Sep 2002, Bill Allombert wrote:
> The magic gnil object is static in GP.

No. It is global in the library.

> This mean a C function is either 'void' and always return nothing (gnil) or
> not 'void' and never return nothing (gnil) but 0 instead.
>
> Consider now the GP script
> f(x)=if(x,1)
> We have
> ? f(1)
> %9 = 1
> ? f(0)
> ?
> This behaviour cannot be emulated by GP2C.

What's wrong with

GEN f(GEN x) { return gcmp0(x)? gnil: gun; }

?

    Karim.
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Karim Belabas                    Tel: (+33) (0)1 69 15 57 48
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