topic Re: Retrieve a macro varible from a different scope in SAS Programming

Retrieve a macro varible from a different scope

sspkmnd — Fri, 08 Sep 2017 16:37:17 GMT

Greetings!

Is there is a way to get a macro variable from a different scope. E.g.

%macro aaa;
    %local a;
    %let a = 123;
    %bbb(a = &a)
%mend;

%macro bbb(a);
    %let a = bbb;
    %put {&a};
    /* here I want to get the value '123' of A macro variable from AAA scope */
%mend;

%aaa;

I know the way to do so using PROC SQL DICTIONARY.MACROS table, but I need a pure SAS way.

Kind regards

Re: Retrieve a macro varible from a different scope

ballardw — Fri, 08 Sep 2017 17:43:20 GMT

At any point in a program only one value a macro variable of a given name will be available.

Since you redefine the macro variable a in the macro BBB to have a value of bbb with a %let at that point the value available by referencing &a is the bbb. I am not sure why you pass a parameter a and then reassign the value as that is pretty nonsensical.

If you want the value of a from macro aaa either pass it to bbb and don't overwrite it with a let or use a different parameter name:

%macro aaa;
    %local a;
    %let a = 123;
    %bbb(b = &a)
%mend;

%macro bbb(b);
    %let a = bbb;
    %put {&b};
    /* here I want to get the value '123' of A macro variable from AAA scope */
%mend;

%aaa;

will do what you want.

Another option would be in the macro AAA to create a global macro variable suchas %global AAA_A;

and assign that the local a value: %let AAA_A = &a; and then in the bbb macro reference the global variable &AAA_A.

Personally I would pass the value I want as a parameter and most likely with a different name unless you actually want the bbb macro to modify the value for use inside the macro aaa.

Re: Retrieve a macro varible from a different scope

sspkmnd — Tue, 07 Aug 2018 21:15:24 GMT

For anyone interested in the answer, Scott Bass open-sourced a macro (originally Written by Tom Abernathy (via SAS-L posting), see header for more details) to utilize the above problem (implemented via SASHELP.VMACRO in a pure SAS Macro).