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For macro variable, under what situation I can omit ampersand?

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Frequent Contributor
Posts: 133

For macro variable, under what situation I can omit ampersand?

I do see couple of examples that macro variables don't have ampersand in front of them when they are referenced.

Can you tell me under what scenario, this rule applies?

Super User
Posts: 10,500

Re: For macro variable, under what situation I can omit ampersand?

I would be interested in seeing where you have found that. Any macro variable I've run across is always preceded with the ampersant. Is it possibly you are confusing a datastep automatic variable such as _n_ or _infile_ with a macro variable?

Super User
Posts: 5,083

Re: For macro variable, under what situation I can omit ampersand?

There are just a handful of cases.  Here are the ones I can think of off the top of my head.

In a DATA step, CALL SYMPUT and SYMGET both expect to see the name of a macro variable.  So the ampersand should be omitted (although since it's in a DATA step, quotes would distinguish between a DATA step variable vs. a text string).  For example, both of these create a macro variable &SALES:

varname='sales';

call symput('sales', 'Friday');

call symput(varname, 'Friday');

Other than that, the only case I can think of is the %superq function.  It also expects the name of a macro variable.  For example:

data _null_;

call symput('measure', 'S&P 500 Index');

run;

%let measure = superq(measure);

title "&measure";

This would quote the &P, so that resolving &measure does not trigger a search for the macro variable &P.

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