Format function after parsing

src/ast.cpp

@@ -1,15 +1,30 @@
 #include "ast.h"
 
+#include <sstream>
+
 namespace AST {
     std::string ReturnStatement::formatted() {
-        return "ReturnStatement";
+        std::stringstream out{ "" };
+        out << "return ";
+        out << this->m_expr->formatted();
+        out << ";";
+        return out.str();
     }
 
     std::string IntLiteralExpression::formatted() {
-        return "IntLiteral";
+        std::stringstream out{ "" };
+        out << this->m_value;
+        return out.str();
     }
 
     std::string Function::formatted() {
-        return "Function";
+        std::stringstream out{ "" };
+        out << "Function() {\n";
+        for (auto& statement : this->m_statements) {
+            out << "  " << statement->formatted() << "\n";
+        }
+
+        out << "}";
+        return out.str();
     }
 }