program foo()
	var i:=1;
	var s1 := struct{i:=i};
	var s2 := struct{};
	var s3 := struct{};
	var s4 := struct{};
	s2.+i := i;
	s3.insert("i",i);
	s4["i"]:=i;
	i+=1;
	print(i);
	print(s1); // structs should not change
	print(s2);
	print(s3);
	print(s4);
endprogram