Question

Solved. See footnote.

            /*check regex*/
            go = 1; 
            i = 1; 
            do while (go = 1);
                set braw.regex point = i;
                    if (upcase(fname) = upcase("&var.")) then do;

                        put format1 " one"; /*format1 is a field of braw.regex, properties says character length 30*/
                        if format1 = '/\d{8}/' then put 'hello world one'; else put 'good bye world one';
                        %check1(&data, format1, &var) 


                    end;
                    else i = i+1;  

            end;

      /*check1 passes regex, string, true false to check_format*/
%macro check_format(regex, string, truefalse);

    pattern = prxparse(&regex.);
    truefalse = prxmatch(pattern, &string); 
    put &regex " " &string " " &truefalse "post";
%mend;

So sorry about the lack of indentation – stackover flow seems to be being buggy or something.

This outputs

 /\d{8}/ one
good bye world one

apparently format isn’t a string. So it then fails the prxparse, as it’s looking for a string input.
Any idea of what I do?

I was thinking I could use a macro variable to put quotes around it, perhaps using:

call symput('mymacrovar', format1);
%let mymacrovar = "&mymacrovar"; 

but that symput does nothing.

Solved:
It was being read as a string. On the CSV file that the regex dataset was being read from, there were additional spaces between the commas, making the string ‘ /\d{8}/’ which prxparse doesn’t like.

Answer 1

It was being read as a string. On the CSV file that the regex dataset was being read from, there were additional spaces between the commas, making the string ‘_/\d{8}/’ (underscore denoting a space) which prxparse doesn’t like.