why doesn't %let create a local macro variable?

Question

I always thought that %let creates a local variable if used inside of %macro . . . %mend

But when I run this code , the SAS log shows GLOBAL TESTVAR value1

%let testVar = value2; 
%macro test; 
%let testVar = value1; 
%mend;   

%test 

%put _all_;

So, I can't understand why the value of the global variable testVar changed to value1 . I was expecting it to be unchanged value2 . The %let statement inside the %macro should have impacted ONLY the local symbol table.

SAS documentation says:

When the macro processor executes a macro program statement that can create a macro variable, the macro processor creates the variable in the local symbol table if no macro variable with the same name is available to it

Answer 1

The key is 'if no macro variable with the same name is available to it' - in this case, a macro variable with the same name is available, because you've already defined testVar as a global.

You can either give it a name that isn't shared with a global, or explicitly declare it as local:

%let testVar = value2; 
%macro test; 
    %local testVar;
    %let testVar = value1; 
%mend;   

%test