You can't, AFAIK. Your best solution is to do separate selects for each variable, something like this code, not tested:

Do SelectAccInlist with 16,10,12,15,8,1

Procedure SelectAccInlist
LPARAMETER ln1,ln2,ln3,ln4,ln5,ln6,ln7,ln8,ln9 && make sure the number is big enough
LOCAL lnMax,lnCust
select customer_id from Customer where .F. into cursor curCustormer && Create empty cursor
lnMax=PCOUNT()
for X=1 to lnMax
  lnCust=EVAL('LN'+LTRIM(STR(X,2,0)))
  select customer_id from Customer where customer_id=lnCust into cursor curTemp
  select curCustomer
  append from dbf('curTemp')
endfor
endproc

> from Customer ;
> where customer_id in (16, 10, 12, 15, 8, 1) ;
> into cursor curCustormer

>

>select customer_id  ;
>  from Customer ;
> where customer_id in (16, 10, 12, 15, 8, 1) ;
>  into cursor curCustormer
>

>
>How can I order the result cursor according to data in the set of inlist expressions
>
>Thank in advance
>
>Ali Altun