symget.sas

%macro symget
/*----------------------------------------------------------------------
Get value for macro variable that is hidden by local macro variable
----------------------------------------------------------------------*/
(mvar        /* Macro variable name */
,include=    /* Space delimited list of macro scopes to search */
,exclude=    /* Space delimited list of macro scopes to ignore */
,recurse=    /* Used internally by the macro  */
);
/*----------------------------------------------------------------------
Use SASHELP.VMACRO to pull value for a macro variable that is hidden by
local macro variables with the same name.
-----------------------------------------------------------------------
$Calls to: -none-
-----------------------------------------------------------------------
Usage:

%* Allow GMV to serve as default value ;
%if %bquote(&MVAR) = %then %let mvar=%symget(mvar);

%* Allow both GMV and parameter style macro calls ;
%macro aesumm(dsnin=,dsnut=,sev=);
  %local macro;
  %let macro=&sysmacroname;
  %if %bquote(&dsnin=) %then %let dsnin=%symget(dsnin,exclude=&macro);
  %if %bquote(&dsnut=) %then %let dsnut=%symget(dsnut,exclude=&macro);
  %if %bquote(&sev=) %then %let sev=%symget(sev,exclude=&macro);
   ....
%mend aesumm;

------------------------------------------------------------------------
Notes:
- Default to finding GLOBAL macro variable.
- Set SYSRC=1 when macro variable not found.
- Macro will call itself recursively to eliminate extra trailing blanks
  pulled from SASHELP.VMACRO.
-----------------------------------------------------------------------
History:

2011/04/05 abernt  Creation
----------------------------------------------------------------------*/
%local macro did rc where scope name value offset;
%let macro=&sysmacroname;

%if "&recurse"="0" %then %do;
%*----------------------------------------------------------------------
Return raw VALUE including any trailing spaces from SASHELP.VMACRO as
the result of the macro call. Stop when all observations are read or 
OFFSET=0 indicates that the start of another instance variable has begun.
-----------------------------------------------------------------------;
  %let where=%upcase(name="&mvar" and scope="&include");
  %let did=%sysfunc(open(sashelp.vmacro(where=(&where))));
  %syscall set(did);
  %if 0=%sysfunc(fetch(&did)) %then %do;
    %do %until(%sysfunc(fetch(&did)) or 0=&offset);&value.%end;
  %end;
  %let rc=%sysfunc(close(&did));
%end;
%else %if %bquote(&mvar)^= %then %do;
%*----------------------------------------------------------------------
Use FINDW() to filter SCOPE.  Include this macro in EXCLUDE list.
Fetch first observation to get SCOPE and NAME. Call this macro
recursively to retrive value into local macro variable.
Return value of local macro variable.
-----------------------------------------------------------------------;
  %if %length(&include) %then %let where=findw("&include",scope,'','ir');
  %else %let where=not findw("&macro &exclude",scope,'','ir');
  %let where=name=%upcase("&mvar") and &where;
  %let did=%sysfunc(open(sashelp.vmacro(where=(&where))));
  %syscall set(did);
  %let rc=%sysfunc(fetch(&did));
  %let did=%sysfunc(close(&did));
  %if (0=&rc) %then %do;
    %let value=%&macro(&name,include=&scope,recurse=0);
&value.
  %end;
%end;

%*----------------------------------------------------------------------
Set SYSRC=1 to indicate macro variable not found.
-----------------------------------------------------------------------;
%let sysrc=%eval(%bquote(&name)=);

%mend symget;