How to suppress infinite loop note when using "IF 0 THEN SET"

Question

To 'copy' the PDV structure of a data set, it has been advised to "reference a data set at compile time" using

if 0 then set <data-set>

For example,

data toBeCopied;
    length var1 $ 4. var2 $ 4. ;
    input var1 $ var2 $;

    datalines;
    this  is
    just  some
    fake  data 
    ;
run;

data copyPDV;
    if 0 then set toBeCopied;

    do var1 = 'cutoff' ;
        do var2 =  'words';
            output;
        end;
    end;    
run;

When you run this, however, the following NOTE appears in the log:

NOTE: DATA STEP stopped due to looping.

This is because the data step never reaches the EOF marker and gets stuck in an infinite loop, as explained in Data Set Looping. (It turns out the DATA step recognizes this and terminates the loop, hence the NOTE in the log).

It seems like usage of the if 0 then set <data-set> statement is a longstanding practice, dating as far back as 1987. Although it seems hacky to me, I can't think of another way to produce the same result (i.e. copying PDV structure), aside from manually restating the attribute requirements. It also strikes me as poor form to allow ERRORs, WARNINGs, and NOTEs which imply unintended program behavior to remain in the log.

Is there way to suppress this note or an altogether better method to achieve the same result (i.e. of copying the PDV structure of a data set)?

If you include a stop; statement, as in

if 0 then do;
        set toBeCopied;
        stop;
    end;

the NOTE still persists.

Trying to restrict the SET to a single observation also seems to have no effect:

if 0 then set toBeCopied (obs=1);

Answer 1

Normally SAS will terminate a data step at the point when you read past the input. Either of raw data or SAS datasets. For example this data step will stop when it executes the SET statement for the 6th time and finds there are no more observations to read.

data want;
  put _n_=;
  set sashelp.class(obs=5);
run;

To prevent loops SAS checks to see if you read any observations in this iteration of the data step. It is smart enough not to warn you if you are not reading from any datasets. So this program does not get a warning.

data want ;
  do age=10 to 15;
    output;
  end;
run;

But by adding that SET statement you triggered the checking. You can prevent the warning by having a dataset that you are actually reading so that it stops when it reads past the end of the actual input data.

data want;
  if 0 then set sashelp.class ;
  set my_class;
run;

Or a file you are reading.

data want ;
  if 0 then set sashelp.class ;
  infile 'my_class.csv' dsd firstobs=2 truncover ;
  input (_all_) (:) ;
run;

Otherwise add a STOP statement to manually end the data step.

data want ;
  if 0 then set sashelp.class;
  do age=10 to 15;
   do sex='M','F';
    output;
   end;
  end;
  stop;
run;