Add CMake file and code for post 4

04/main.cpp

@@ -0,0 +1,39 @@
+#include "ast.hpp"
+#include "parser.hpp"
+#include "type.hpp"
+
+void yy::parser::error(const std::string& msg) {
+    std::cout << "An error occured: " << msg << std::endl;
+}
+
+extern std::vector<definition_ptr> program;
+
+void typecheck_program(const std::vector<definition_ptr>& prog) {
+    type_mgr mgr;
+    type_env env;
+
+    type_ptr int_type = type_ptr(new type_base("Int")); 
+    type_ptr binop_type = type_ptr(new type_arr(
+                int_type,
+                type_ptr(new type_arr(int_type, int_type))));
+
+    env.bind("+", binop_type);
+    env.bind("-", binop_type);
+    env.bind("*", binop_type);
+    env.bind("/", binop_type);
+
+    for(auto& def : prog) {
+        def->typecheck_first(mgr, env);
+    }
+
+    for(auto& def : prog) {
+        def->typecheck_second(mgr, env);
+    }
+}
+
+int main() {
+    yy::parser parser;
+    parser.parse();
+    typecheck_program(program);
+    std::cout << program.size() << std::endl;
+}