@@ 18,9 18,11 @@ fn main() {
   # this should work, s is mutable
   let tup: (int, I) = (1, s)
   tup.1.foo()
+  println(s.i)
 }
 
 @extern(import: "fmt", symbol: "Println")
 fn println(v: int)
 
 #=1
+#=2

@@ 628,7 628,6 @@ func (t *translator) goTypeExprFor(T semantic.Type) goast.Expr {
 		}
 		for i, field := range T.Fields {
 			st.Fields.List[i] = &goast.Field{
-				// TODO: for now, always unexported?
 				Names: []*goast.Ident{{Name: t.resolver.NameForTuple(i, false)}},
 				Type:  t.goTypeExprFor(field),
 			}


@@ 662,6 661,9 @@ func (t *translator) convertExprFromTo(expr goast.Expr, fromT, toT semantic.Type
 	// to it (as the rules for assignability are the same). Only thing is if one of the methods
 	// is satisfied by a ref function, the address of expr must be returned instead.
 	if semantic.AsInterfaceType(toT) != nil {
+		if st := semantic.AsStructType(fromT); st != nil && st.Ctx == semantic.Mutable {
+			return &goast.UnaryExpr{Op: gotoken.AND, X: expr}
+		}
 		return expr
 	}