怎样有条件的推出宏循环？

shiyiming

再宏当中为什么不可以用 %if  %then leave;跳出宏循环呢？

shiyiming

[code:01249]%macro check(parm);
   %local status;
   %if &parm= %then %do;
       %put ERROR:  You must supply a parameter to macro CHECK.;
       %goto exit;
   %end;

   more macro statements that test for error conditions

   %if &status > 0 %then %do;
       %put ERROR:  File is empty.;
       %goto exit;
   %end;

   more macro statements that generate text

   %put Check completed successfully.;
%exit: %mend check;[/code:01249]

shiyiming

因为leave不是宏语句,呵呵呵.