Fix in op checker

checker/checker.go

@@ -341,7 +341,7 @@ func (v *visitor) BinaryNode(node *ast.BinaryNode) (reflect.Type, info) {
 			if l == nil { // It is possible to compare with nil.
 				return boolType, info{}
 			}
-			if !isAny(l) && !isInteger(l) {
+			if !isAny(l) && !l.AssignableTo(r.Elem()) && !(isInteger(l) && isInteger(r.Elem())) {
 				return v.error(node, "cannot use %v as type %v in array", l, r.Elem())
 			}
 			return boolType, info{}

checker/checker_test.go

@@ -55,8 +55,10 @@ var successTests = []string{
 	"(Any ? 0 : nil) == 0",
 	"(Any ? nil : nil) == nil",
 	"!(Any ? Foo : Foo.Bar).Anything",
-	"Int in ArrayOfFoo",
-	"Int not in ArrayOfFoo",
+	"Int in ArrayOfInt",
+	"Int not in ArrayOfAny",
+	"String in ArrayOfAny",
+	"String in ArrayOfString",
 	"String in Foo",
 	"String in MapOfFoo",
 	"String matches 'ok'",