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SAS MACRO Quote issue: Passing a string using a macro as a macro parameter

Is it possible to pass a string with a macro trigger as a macro parameter? See sample code below:

options mprint;
%let string5='%abc%def%';
%macro test(string);
data _null_;
    call execute('%test2('||&string.||')');
run;
%mend;

%macro test2(string2);
    data test3;
        a=%str(%')&string2.%str(%');
    run;
%mend;

%test(&string5);

This code worked successfully, but it tried to call the% abc and% def macros, which resulted in warnings.

If I tried to put it in a quote to mask the string, it gave a syntax error like below:

options mprint;

    %let string5='%abc%def%';
    %macro test(string);

    data _null_;
        call execute('%test2('||%superQ(string)||')');
    run;
    %mend;

    %macro test2(string2);
        data test3;
            a=%str(%')&string2.%str(%');
        run;
    %mend;

    %test(&string5);

ERROR 22-322: Syntax error, expecting one of the following: a name, a quoted string, a numeric constant, a datetime constant, a missing value, arrayname, (, +, -, INPUT, NOT, PUT, ^, _NEW_, ~.

Is there a way to fix this without warnings? Thanks in advance!

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4 answers


Try the following:



%let string5='%abc%def%';
%macro test(string);
data _null_;
    call execute('%test2('||%nrstr("&string.")||')');
run;
%mend;

%macro test2(string2);
    data test3;
        a=%nrquote(&string2.);
    run;
%mend;

%test(&string5);
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Usually macros are usually fairly simple to protect against special characters. For example, you can use a function %superq()

to specify an existing value for macro variables.

where name like %unquote(%str(%')%superq(parm1)%str(%'))

Or use a function symget()

in a data step to get the value without having to expand the macro at all.

pattern = quote(symget('parm1'),"'");

But the tricky part is calling the macro. You need to protect symbols in order to trigger the macro call. You can use similar functions in a macro call.



One useful task is to instruct users to pass the parameter value as a quoted string, and then the macro code you can remove the quotes when they are not needed.

%macro mymacro(parm1=);
  %let parm1=%qsysfunc(dequote(&parm1));
  ...
%mend;
%mymacro(parm1='fred%')

Or you can ask them to pass the value by name.

%macro mymacro(mvar=);
  %local pattern ;
  %let pattern=%superq(&mvar);
  ...
%mend ;

%let my_pattern=%qsysfunc(dequote('fred%'));
%mymacro(mvar=my_pattern)
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If this already works the way you want and you just want to suppress that one warning message, you might want to consider installing option nomerror;

before running the section of the code in question and then reinstalling it again.

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Just update to the final solution I choose. I gave up on the way of passing macro parameters between different macros, instead I passed the name of the macro variable as a string. Code examples are given below:

options mprint;
%let string5='%abc%def%';

%macro test(string);
data _null_;
    call execute('%test2('||&string.||')');
run;
%mend;

%macro test2(string2);
    data test3;
        a=&&&string2.;
    run;
%mend;

%test('string5');
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