[metapost] Processing comma separated values

[Aditya Mahajan]

On Fri, 26 Feb 2010, Taco Hoekwater wrote:

> Aditya Mahajan wrote:
>> What is the canonical way of processing a list of comma separated values in 
>> metapost. I want to write a helper macro for the boxes package so that
>
> I do not have time to write a full answer, but the way to
> process a list of argument values is something like this:
>
> def boxsep (text a) =
>   forsuffixes _a=a:
> 	 show _a;
>   endfor
> enddef;

Thanks. Dan Luecking posted a solution offlist that works perfectly.

def boxsep (suffix A,B) (text T) =
   def _prev_suffix = B enddef;
   B.w - A.e
   forsuffixes _S = T:
     = _S.w - _prev_suffix.e
     hide (def _prev_suffix = _S enddef;)
   endfor
enddef;

I had to read the metapost manual carefully to understand why it works.

To metapost,

boxset(a,b)(c,d) is the same as boxset(a,b,c,d).

Thanks you Dan and Taco.

Aditya