Strange behavior when double-ampersand macro variable needs a multiple dot delimiter

[bentleyj1]

Very curious.  I'd sworn there were no trailing blanks in the macro value and I was wrong.

Earlier in the code I created the macro variable with this code figuring it would remove trailing blanks.  The maximum length of tableName is 30 characters and the length of _uniqTable1 was 30 when the trailing blanks are counted.

     %** Get the unique table names.   ;

     select unique strip(tableName) label='Unique Table Name'

     into : _uniqDbTable1

     %if &_nUniqTables > 1 %then -

          : _uniqDbTable&_nUniqTables ;

     from  &project_name._cell_ltr_tables;

So why does %let _table= &&_uniqDbTable&_n remove trailing blanks but the Proc SQL syntax didn't?

If this is a feature of Proc SQL then I'm going to have to be more careful going forward because I use it a lot to create macro variables.

Thanks to all who contributed.

John

[Tom]

%LET removes the spaces because spaces are interpreted as token delimiters.  So %let X=     xxxx        ; is the same as %let X=xxxx;

You do not need that macro logic.  You can let PROC SQL take care of knowing how many macro variables to make. If you have a newer version of SAS then just do not put anything after the hyphen.  If you have an older version then just use some obviously too large value for the upper bound.  SAS will only create the number of macro variables that it needs.  It will also count the number of values for you.

%** Get the unique table names.   ;

select unique tableName

  into :_uniqDbTable1 - :_uniqDbTable9999

  from &project_name._cell_ltr_tables

;

%let _nUniqTables = &sqlobs ;

[jakarman]

John there is a difference in macro language parsing and sas language parsing.  Gergely Bathó already mentioned that.
With the datastep and proc sql you can put literally every kind of character into a macro variable

SAS(R) 9.4 SQL Procedure User's Guide (using macro vars) the trim is explicitly activated with concatenating the content. As it mentioned is not by default.

for the datastep there is new function SAS(R) 9.4 Functions and CALL Routines: Reference, Third Edition (symputx) is trims space and let you control wich symboltable you are using. Be carefull on that one too as local tables can or may not be nested.

The macro quoting (SAS(R) 9.4 Macro Language: Reference, Second Edition - SAS(R) 9.4 Macro Language: Reference, Second Edition (%quote an %unquote) are to be used when you are defining character in a macro-variable that can conflict with the macro-language. Very predictable and constant in behavior.

As rule of thumb: when possible conflicting chars can occur use %nrquote at the moment of defining and %unquote when using.