macro loop does not function with special text string

[funnybunny78]

I have the following Macro code:

%macro LTV_DSCR(file1,file2,var,bins,lm1,lm2,rounding);
%local i j part1 part2;
%let i=1;
%do %while(%scan(%str(&file1), &i) ne);
%let part1=%scan(%str(%&file1), &i);
%let j=1;
%do %while(%scan(%str(%&file2), &j) ne);
%let part2=%scan(%str(%&file2), &j);

..........

%let j=%eval(&j+1);
%end;
%let i=%eval(&i+1);
%end;
%mend LTV_DSCR;

%LTVDSCR(RT OR OF IN MF LO, W SE SW MW NE, LTV, 10, 2.5, 4, 0.1);

The code gives error message:

ERROR: A character operand was found in the %EVAL function or %IF condition where a numeric operand is required. The condition was:
%scan(&file1, &i) ne
ERROR: The condition in the %DO %WHILE loop, %scan(
&file1, &i) ne, yielded an invalid or missing value, . The macro will stop
executing.
ERROR: The macro LTV_DSCR will stop executing.

This only happens when it reaches word like "OR" "NA".  

How should I modify my code?

[Reeza]

Yes, those are reserved words in SAS Macro language, ie OR is logical operator OR, not Oregon as you're likely using it. 

See if these help you out:

https://blogs.sas.com/content/sgf/2014/08/15/macro-quoting-made-easy/

[funnybunny78]

Hi, I tried most macro function suggested in the article, and none works.  Can someone be more specific about how to resolve this issue?

Thanks.

[Astounding]

Actually, you omitted the code that is causing the problem.  It's likely that you can switch from %SCAN to %QSCAN to solve the problem but we may need to see the code indicated by "............"

[PaigeMiller]

The link given specifically shows what to do with OR

If it doesn't work, show us what you tried.

[Reeza]

Make sure you catch all the problematic words, in this case likely:

OR, OF, NE at minimum. 

It helps if you turn on MPRINT/SYMBOLGEN to see issues in the log and it identifies the problematic portion in more detail. 

[Kurt_Bremser]

Replace that macro code with data step code, and it will be a lot easier.

First, wrap the ....... code into its own macro:

%macro do_single(part1,part2,var,bins,lm1,lm2,rounding);
........
%mend;

Then restructure your outer macro:

%macro LTV_DSCR(file1,file2,var,bins,lm1,lm2,rounding);
data _null_;
do i = 1 to countw("&file1", ' ');
  part1 = scan("&file1",i,' ');
  do j = 1 to countw("&file2",' ');
    part2 = scan("&file2",j,' ');
    call execute('%nrstr(%do_single(' !! trim(part1) !! ',' !! trim(part2) !! ",&var,&bins,&lm1,&lm2,&rounding))");
  end;
end;
run;
%mend LTV_DSCR;

For the data step, there is no reason to consider anything in a string a "special word" that needs to be masked.

See this simple example:

%macro do_single(part1,part2,var,bins,lm1,lm2,rounding);
%put &part1;
%put &part2;
%put &rounding;
%mend;

%macro LTV_DSCR(file1,file2,var,bins,lm1,lm2,rounding);
data _null_;
do i = 1 to countw("&file1", ' ');
  part1 = scan("&file1",i,' ');
  do j = 1 to countw("&file2",' ');
    part2 = scan("&file2",j,' ');
    call execute('%nrstr(%do_single(' !! trim(part1) !! ',' !! trim(part2) !! ",&var,&bins,&lm1,&lm2,&rounding))");
  end;
end;
run;
%mend LTV_DSCR;

%LTV_DSCR(RT OR OF IN MF LO, W SE SW MW NE, LTV, 10, 2.5, 4, 0.1);

Abbreviated log from that:

45         %LTV_DSCR(RT OR OF IN MF LO, W SE SW MW NE, LTV, 10, 2.5, 4, 0.1);

NOTE: DATA statement used (Total process time):
      real time           0.00 seconds
      cpu time            0.00 seconds
      

NOTE: CALL EXECUTE generated line.
1         + %do_single(RT,W,LTV,10,2.5,4,0.1)
RT
W
0.1
2         + %do_single(RT,SE,LTV,10,2.5,4,0.1)
RT
SE
0.1