****** 1;

data _null_;
a='3+2';
call execute('data a;a='||quote(a)||';b='||strip(a)||';run;');
run;

****** 2;

data a;
a='3+2';
call symput('b',compress(a));
run;
data a;
set a;
b=input(resolve(%unquote(&b)),best.);
run;