求助 - scan %scan 运行时出现错误

gogotiger

%let t=abc nvberuov, llc||ncvjdi jki, hugh||nwd12, 30vn jdfksj;
%let t2=abc nvberuov llc, ncvjdi jki, hugh nwd12, 30vn jdfksj;
%let y1=%scan(&t., 1, '||');
%let y2=%scan(&t2., 1);
%let y3=%scan(&t2., 1,',');
%put t=&t. y1=&y1.  y2=&y2. y3=&y3.;
data a;
  y4=scan(&t1., 1);
  y5=scan(&t2., 1, ',');
run;
上面的code是为了得到第一个string.

运行后均出现错误，the scan function call has too many arguments. 请教一下，该如何改？
谢谢！！！！