Date:         Fri, 29 Mar 1996 09:49:18 PST
Reply-To:     TWB2%Rates%FAR@GO50.COMP.PGE.COM
Sender:       "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From:         TWB2%Rates%FAR@GO50.COMP.PGE.COM
Subject:      Re: Calling Global Variables Conditionally from a Nested Macro
Comments: To: jcarpent@GNU.UVM.EDU

Joe, try changing &count&countparameter to &&count&countparameter in the inner
macro.  When SAS scans a double ampersand, it stores a single ampersand and
rescans the line.  Thus if &which is 3, &&parm&which scans into &parm3 and the
line is then rescanned so that &parm3 can be resolved.  There are also times
when macro mavens will use &&& and &&&&, and probably even more (although by
the time I get to &&&&&&parm&&&&index&&ptr&num, I look for another approach).
 
&&&&&&parm&&&&index&&ptr&num   assume &num is 5 resolves to
&&&parm&&index&ptr5 assume &ptr5 is 3 and &parm is cat resolves to
&cat&index3  assume &cat is angora and &index3 is Sassy Cat resolves to
angoraSassy Cat
 
 
----------------------[Reply - Original Message]----------------------
 
Sent by:Joe Carpenter <jcarpent@GNU.UVM.EDU>
 I would appreciate any help in calling global variables conditionally
from a nested macro.  The program structure is similar to the following:
 
%global COUNT1 COUNT2 COUNT3 COUNT4 COUNT5;
%macro one (parameters);
 
   macro statements;
   call symput statements to set up global vars;
 
   invoke macro 2 with parameters 1, 2, 3, 4, or 5, depending on which
   global count variable is needed;
%mend macro 1;
 
%macro2 (countparameter);
 
   %if &count&countparameter > 0 %then %do;   e.g., &count3
     program statements;
   %end;
%mend macro2;
 
 
I would appreciate help with the %if statement - how to have the macro
variable be read as &count1 to &count5, depending on invocation.
 
 
 
Joe Carpenter
Data Analyst, Biometry Facility
University of Vermont
(802) 656-0619   email:  jcarpent@zoo.uvm.edu
 
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