Nick Winter answered Hans Baumgartner and Tao Jiang very
fully. He also wrote 
> -forvalues-, on the other hand, takes a numlist.  
This is not quite true. -forvalues- does not 
take an (arbitrary) numlist. That is explicit 
in the syntax and implicit in the examples. It 
is specialised to take ranges, where the definition of 
range is idiosyncratic to -forvalues-, but -- as 
pointed out earlier -- this certainly does not include 
cases in which you wrap around modulo some value, tacit 
or not.  
(This thread is cycling round the issues 
raised in one started on 14 November!) 
Nick 
[email protected] 
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