topic Re: && in SAS Procedures

&&

R_A_G_ — Sat, 16 Nov 2013 21:11:27 GMT

Hello,

Could some explain to me what is the difference between single and double ampersand.

thanks

Re: &&

JerryLeBreton — Sat, 16 Nov 2013 21:42:02 GMT

Try the doco :
Macro Language: Reference

Re: &&

Tom — Sun, 17 Nov 2013 18:00:06 GMT

Multiple && will let the macro processor know that it needs to rescan the token to fully evaluate the macro variable reference. This will allow you to use a macro variable to hold the ame of the variable that you actually what.

%Let name=var1;

%let var1=45;

%let n=1;

%put &&var&n;

%put &&&name;

Re: &&

Tal — Mon, 18 Nov 2013 06:16:34 GMT

&& and & resolve the same value,right?

Re: &&

Amir — Mon, 18 Nov 2013 12:49:16 GMT

Hi,

A double ampersand resolves to a single ampersand. Try using:

options symbolgen;

before @Tom's macro code to see messages in the log explaining what is being resolved.

Regards,

Amir.

Re: &&

Tom — Mon, 18 Nov 2013 15:48:16 GMT

Right, and also trigger the compiler to re-evaluate the result.

So &&var&n --> &var1 --> 45

Re: &&

sassharp — Mon, 18 Nov 2013 16:59:53 GMT

That is Forward Re-scan rule. If you have SAS advanced Certification Book they explained in Chapter 10.

http://www.caliberdt.com/tips/May2006.htm

Re: &&

R_A_G_ — Tue, 19 Nov 2013 02:19:21 GMT

how about &&&name ?

what would this resolves into?

Re: &&

Reeza — Tue, 19 Nov 2013 02:53:58 GMT