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variablessasrefer

Referring to a macro variable already defined

I was going through a SAS code and found the following ways of referencing a macro variable.

  1. &variable_name .
  2. &variable_name

I know that the first way of referencing is the normal way of how we refer to a defined macro variable in sas.

But, could you please explain how does the second way(without period after the macro variable name) is different from the first way

Solution

  • It is the short way to reference a variable. However it makes a difference when concatenating output:

    %let var = My name ;

%put &var.is Paul;
// Output: My name is Paul.

%put &varis Paul;
// Output: WARNING: Apparent symbolic reference VARIS not resolved.
// &varis Paul

    Another example where you definitely need a .:

    %let lib = sashelp;
data temp;
  set &lib..class;
run;

    I would recommend to always use the variant &variable.. Because it is clear where the variable ends.