add list interface with iterator

c_os/user/lib/List.h

@@ -0,0 +1,68 @@
+#ifndef __LIST_INCLUDE_H_
+#define __LIST_INCLUDE_H_
+
+#include "lib/OutStream.h"
+
+// Define the list interface for ArrayList/LinkedList implementations with support for Iterators/ranged based for loops
+
+template<typename List>
+class ListIterator {
+private:
+    using ValType = typename List::ValType;
+
+    ValType* ptr;
+
+public:
+    ListIterator(ValType* ptr) : ptr(ptr) {}
+
+    // I only implement the least necessary operators
+    ListIterator& operator++() {
+        this->ptr = this->ptr + 1;
+        return *this;
+    }
+
+    ValType* operator->() {
+        return this->ptr;
+    }
+
+    ValType& operator*() {
+        return *this->ptr;
+    }
+
+    bool operator==(const ListIterator& other) const {
+        return this->ptr == other.ptr;
+    }
+
+    bool operator!=(const ListIterator& other) const {
+        return !(*this == other);  // Use our == implementation
+    }
+};
+
+template<typename T>
+class List {
+public:
+    using ValType = T;
+    using Iterator = ListIterator<List<T>>;
+
+    virtual Iterator begin() = 0;
+    virtual Iterator end() = 0;
+
+    virtual unsigned int insert(T e) = 0;
+    virtual unsigned int insert_at(T e, unsigned int i) = 0;
+
+    virtual T remove_at(unsigned int i) = 0;
+    virtual T remove_first() = 0;
+    virtual T remove_last() = 0;
+    virtual bool remove(T e) = 0;
+
+    virtual T get(unsigned int i) const = 0;
+    virtual T first() const = 0;
+    virtual T last() const = 0;
+
+    virtual bool empty() const = 0;
+    virtual unsigned int size() const = 0;
+
+    virtual void print(OutStream& out) const = 0;
+};
+
+#endif