Start working on type code

code/compiler/03/type.hpp

@@ -0,0 +1,39 @@
+#pragma once
+#include <memory>
+#include <map>
+
+struct type {
+    virtual ~type() = default;
+};
+
+using type_ptr = std::shared_ptr<type>;
+
+struct type_var : public type {
+    std::string name;
+
+    type_var(std::string n)
+        : name(std::move(n)) {}
+};
+
+struct type_id : public type {
+    int id;
+
+    type_id(int i) 
+        : id(i) {}
+};
+
+struct type_arr : public type {
+    type_ptr left;
+    type_ptr right;
+
+    type_arr(type_ptr l, type_ptr r)
+        : left(std::move(l)), right(std::move(r)) {}
+};
+
+struct type_mgr {
+    int last_id = 0;
+
+    std::string new_type_name();
+    type_ptr new_type();
+    type_ptr new_arrow_type();
+};