[ox/std] Improve Vector::iterator to better conform to std::vector::iterator

(synced from 68f829ff2d)

src/ox/std/iterator.hpp

@@ -9,6 +9,8 @@
 #pragma once
 
 #ifndef OX_USE_STDLIB
+#include "types.hpp"
+
 namespace std {
 
 struct input_iterator_tag {
@@ -29,12 +31,14 @@ struct random_access_iterator_tag: public bidirectional_iterator_tag {
 struct contiguous_iterator_tag: public random_access_iterator_tag {
 };
 
-template<typename Category, typename T>
+template<typename Category, typename T, typename DiffType = std::ptrdiff_t,
+         typename PointerType = T*, typename ReferenceType = T&>
 struct iterator {
 	using iterator_category = Category;
 	using value_type = T;
 	using pointer = T*;
 	using reference = T&;
+	using difference_type = DiffType;
 };
 
 }