From 2cecb456bb5074f4969d0cd362fc27c2e2c5b222 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Grodzi=C5=84ski?= <rafal.grodzinski@gmail.com>
Date: Sun, 1 Jun 2025 23:39:45 +0900
Subject: [PATCH] Return statement

---
 src/Parser.cpp    | 24 ++++++++++++++++++++++++
 src/Parser.h      |  1 +
 src/Statement.cpp |  7 +++++++
 src/Statement.h   |  1 +
 4 files changed, 33 insertions(+)

diff --git a/src/Parser.cpp b/src/Parser.cpp
index 9cb91a4..aba3907 100644
--- a/src/Parser.cpp
+++ b/src/Parser.cpp
@@ -29,6 +29,12 @@ shared_ptr<Statement> Parser::nextStatement() {
             return statement;
     }
 
+    {
+        shared_ptr<Statement> statement = matchReturnStatement();
+        if (statement->isValid())
+            return statement;
+    }
+
     {
         shared_ptr<Statement> statement = matchExpressionStatement();
         if (statement->isValid())
@@ -78,6 +84,24 @@ shared_ptr<Statement> Parser::matchBlockStatement() {
     return make_shared<Statement>(Statement::Kind::BLOCK, nullptr, nullptr, nullptr, statements, "");
 }
 
+shared_ptr<Statement> Parser::matchReturnStatement() {
+    if (tokens.at(currentIndex).getKind() != Token::Kind::RETURN)
+        return make_shared<Statement>(Statement::Kind::INVALID, make_shared<Token>(tokens.at(currentIndex)), nullptr, nullptr, vector<shared_ptr<Statement>>(), "");
+    
+    currentIndex++;
+
+    shared_ptr<Expression> expression = term();
+    if (!expression->isValid())
+        expression = nullptr;
+    
+    if (tokens.at(currentIndex).getKind() != Token::Kind::NEW_LINE)
+        return make_shared<Statement>(Statement::Kind::INVALID, make_shared<Token>(tokens.at(currentIndex)), nullptr, nullptr, vector<shared_ptr<Statement>>(), "");
+    
+    currentIndex++; // new line
+    
+    return make_shared<Statement>(Statement::Kind::RETURN, nullptr, expression, nullptr, vector<shared_ptr<Statement>>(), "");
+}
+
 shared_ptr<Statement> Parser::matchInvalidStatement() {
     return make_shared<Statement>(Statement::Kind::INVALID, make_shared<Token>(tokens.at(currentIndex)), nullptr, nullptr, vector<shared_ptr<Statement>>(), "");
 }
diff --git a/src/Parser.h b/src/Parser.h
index 5ad626a..fe39db2 100644
--- a/src/Parser.h
+++ b/src/Parser.h
@@ -17,6 +17,7 @@ private:
 
     shared_ptr<Statement> matchFunctionDeclarationStatement();
     shared_ptr<Statement> matchBlockStatement();
+    shared_ptr<Statement> matchReturnStatement();
     shared_ptr<Statement> matchInvalidStatement();
 
     shared_ptr<Statement> matchExpressionStatement();
diff --git a/src/Statement.cpp b/src/Statement.cpp
index d54d652..2049e75 100644
--- a/src/Statement.cpp
+++ b/src/Statement.cpp
@@ -31,6 +31,13 @@ string Statement::toString() {
         }
         case FUNCTION_DECLARATION:
             return "FUNCTION " + name + "\n" + blockStatement->toString() + "\n;";
+        case RETURN: {
+            string value = "RETURN";
+            if (expression != nullptr) {
+                value += " " + expression->toString();
+            }
+            return value;
+        }
         case INVALID:
             return "INVALID";
     }
diff --git a/src/Statement.h b/src/Statement.h
index 070719f..362521c 100644
--- a/src/Statement.h
+++ b/src/Statement.h
@@ -14,6 +14,7 @@ public:
         EXPRESSION,
         BLOCK,
         FUNCTION_DECLARATION,
+        RETURN,
         INVALID
     };