got it down to this:
void main() { multiset m=(<"Stone","2","%70">); foreach(m;string k;int one) { if(k=="%70") { m[k]=0; break; } }
multiset direct_add=m-(<>); werror("%O %O\n\n", (array)direct_add, direct_add); }
without the foreach, the error disappears...
greetings, martin.