topic Macro parameter in New SAS User

Macro parameter

SASPhile — Wed, 17 Jul 2019 15:57:25 GMT

Is there a way to pass macro parameters as shwon below where it can handle a straight assignment or a if statement:

%macro test(var1=);

%mend test;

%test(var1=abc);

%test(var1= (if x=1 then var1='blah';

else var1='blah blah');

);

Re: Macro parameter

tomrvincent — Wed, 17 Jul 2019 16:31:27 GMT

I've often found it works to put double quotes around it and then remove them in the macro.

Example:
%test(var1="(if x=1 then var1='blah'; else var1='blah blah');" );

Then use
%let newvar1=%qsysfunc(compress(&var1,%str(%")));
to remove the double-quotes.

Re: Macro parameter

SASPhile — Wed, 17 Jul 2019 16:35:22 GMT

var1="(if x=1 then var1='blah'; else var1='blah blah');"

Isnt this double assignment for the same variable Var1 ?

Var1="(if x=1 then var1='blah'; else var1='blah blah');"

Re: Macro parameter

Tom — Wed, 17 Jul 2019 17:09:58 GMT

@SASPhile wrote:

var1="(if x=1 then var1='blah'; else var1='blah blah');"

Isnt this double assignment for the same variable Var1 ?

Var1="(if x=1 then var1='blah'; else var1='blah blah');"

NO. The first use of VAR1 is the name of the macro parameter. The second use depends on how &VAR1 is used in the macro, but most likely it is referencing a dataset variable named var1.

Re: Macro parameter

Tom — Wed, 17 Jul 2019 17:11:34 GMT

@tomrvincent wrote:
I've often found it works to put double quotes around it and then remove them in the macro.

Example:
%test(var1="(if x=1 then var1='blah'; else var1='blah blah');" );

Then use
%let newvar1=%qsysfunc(compress(&var1,%str(%")));
to remove the double-quotes.

Don't use COMPRESS() as it will also remove any quotes that you want to keep. Instead use DEQUOTE(). If the value is not enclosed in quotes then DEQUOTE() will not change it.

%sysfunc(dequote(&var1))

Re: Macro parameter

Tom — Wed, 17 Jul 2019 17:19:12 GMT

It is the sem-colons that are going to cause trouble.

You need to quote the value in the call and then remove the quoting when using the value.

Either use macro quoting.

%macro test(var1);
...
%unquote(&var1)
...
%mend test;
%test(var1=%str(if x=1 then var1='blah';else var1='blah blah';))
%test(var1=if x=1 then var1='blah'%str(;)else var1='blah blah'%str(;))

Or use you can use actual quotes. Note that with this method you can call it with either macro quoting or actual quoting.

%macro test(var1);
...
%sysfunc(dequote((&var1))
...
%mend test;
%test(var1="if x=1 then var1='blah';else var1='blah blah';")
%test(var1='if x=1 then var1="blah";else var1="blah blah";')
%test(var1='if x=1 then var1=''blah'';else var1=''blah blah'';')

%test(var1=%str(if x=1 then var1='blah';else var1='blah blah';))
%test(var1=if x=1 then var1='blah'%str(;)else var1='blah blah'%str(;))

Re: Macro parameter

tomrvincent — Wed, 17 Jul 2019 18:19:11 GMT

Different 'variables'.

Best to have different names for your macro variables and dataset columns.

Maybe MacroVar1="(if x=1 then colvar1='blah'; else colvar1='blah blah');" would be better.