| Improving Program Efficiency with Macro Variables |
| Creating Your Own Macro
Variables |
| Unresolved Macro Variable References
What happens if a macro variable reference cannot be resolved? For example, suppose you revised your program to include a macro variable but misspelled the macro variable name when referencing it. What happens when you submit this program? %let year=1999;
title "Temporary Employees for &year";
data hrd.newtemp;
set hrd.temp;
if year(enddate)=&yera;
run;
proc print data=hrd.newtemp;
run;
When SAS software encounters a macro variable reference but cannot locate a macro variable by that name, the reference is left unresolved and a warning message, such as the following, is written to the SAS log. |
SAS Log
2 %let year=1999;
3 title "Temporary Employees for &year";
4 data hrd.newtemp;
5 set hrd.temp;
6 if year(enddate)=&yera;
-
390
WARNING: Apparent symbolic reference YERA not
resolved.
NOTE: The SAS System stopped processing this step
because of errors.
NOTE: The DATA statement used 0.78 seconds.
6 proc print data=hrd.newtemp;
7 title "Temporary Employees for &year";
8 run;
ERROR 390-185: Expecting a relational or an
arithmetic operator.
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| SAS software continues scanning, but an unresolved macro variable reference
often results in a syntax error. Syntax errors often occur because the ampersand
that appears in an unresolved macro variable reference cannot be used in
most SAS statements.
If you receive warning messages about unresolved macro variable references, check that
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Copyright © 2002 SAS Institute Inc.,
Cary, NC, USA. All rights reserved.