Re: How can I keep these values local to my function?

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

Hi,

  just add my(One, Two, Three, Four, Five, Six) to the body of f.
Those will be lexically scoped to f.

Cheers,

      K.B.

* Joe Slater [2024-09-11 03:15]:
> I want to be able to specify binary combinations of options the way that,
> e.g., vecsort() does. I couldn't see a way to do that so I created a
> function, makeoptions(), that returns a vector in the form
> ["a=1","b=2",...] and I use eval() on that vector to create those variables
> within my function. My problem is that eval() creates them with global
> scope, and I can't see a way to make them local.
> 
> /* Takes a string containing a list of option names and a number whose
> binary digits represents those options. Returns variables set accordingly.
> */
> makeoptions(s="",options=0)=
> {
>     if(s=="",return());
>     my(v=strsplit(s," "));
>     return(vector(#v,i,(Str(v[i],"=",bitand(2^(i-1),options)<>0))))
> }
> /* A function that uses makeoptions() */
> f(n)={
>     my(a=eval(makeoptions("One Two Three", n)));
>     my(b=eval(makeoptions("Four Five Six", n+1)));
>     print("a=",One,Two,Three);
>     print("b=",Four,Five,Six);
>     }
> 
> Here's the output from my function:
> (10:31) > f(2)
> a=010
> b=110
> (10:31) > One \\ Should be undefined
> %2 = 0
> (10:32) > Four \\ Should be undefined
> %3 = 1
> Is there a way to make these variables local, or another way to achieve
> what I want: local named variables set at run time without having a routine
> along the lines of Opt1=bitand(options,1); Opt2=bitand(options,2); ...
> 
> Thanks,
> Joe Slater
-- 
Pr. Karim Belabas, U. Bordeaux, Vice-président en charge du Numérique
Institut de Mathématiques de Bordeaux UMR 5251 - (+33) 05 40 00 29 77
http://www.math.u-bordeaux.fr/~kbelabas/