Apparent error in "%* Macro Comment Macro Statement" documentation

[mkeintz]

This is not exactly a request for solutions, but an invitation for comments.  Maybe someone has brought this to SAS' attention already.

The discussion starting out the documentation for %* Macro Comment Macro Statement is not being challenged here.  Instead I am focusing on an example in this section intended to show that an ordinary comment statement (beginning with * or with COMMENT) does NOT mask the comment content from the macro processor (hence the need for /* */ or %*).  It does show that property alright, but a little more pathologically than intended.

The example is as follows:

%macro verdata(in, thresh);
    *%let thresh = 5;
    /* The preceding SAS comment does not hide the %let statement
        as does this type of SAS comment.
        %let thresh = 6;
    */
   %if %length(&in) > 0 %then %do;
         %* infile given;
      data check;
           /* Jim's data */
         infile ∈
         input x y z;
            * check data;
         if x<&thresh or y<&thresh or z<&thresh then list;
      run;
   %end;
   %else %put Error: No infile specified;
%mend verdata;
%verdata(ina, 0)

which the documentation asserts will produce this sas program:

DATA CHECK;
   INFILE INA;
   INPUT X Y Z;
      * CHECK DATA;
   IF X<5 OR Y<5 OR Z<5 THEN LIST;
RUN;

Nope.  It actually produces this sas code: 

* data check;
infile ina;
input x y z;
* check data;
if x<5 or y<5 or z<5 then list;
run;

... and a lot of error messages in the sas log.

This is ironic, since while successfully showing that the *%let thresh=5; causes macro processor to ignore the asterisk and assign a value of 5 to thresh, it also shows that the resulting %let macro statement absorbs the semicolon, thereby converting the subsequent data statement into a comment (pesky little asterisk left untouched by macro).

The latter consequence was overlooked in the documentation.  I don't think the example was actually tested (also revealed by the fact that the purported resulting code is capitalized even though the source code inside the macro wasn't).

[Tom · Accepted solution]

You are right.

Click on the Feedback link on that documentation page and report the issue to the documentation team.  They are very happy to get constructive feedback like this.

[mkeintz]

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@Tom wrote:

You are right.

Click on the Feedback link on that documentation page and report the issue to the documentation team.  They are very happy to get constructive feedback like this.

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Done.