From 780d4d03b57abea093b578b85bc6886fe1512468 Mon Sep 17 00:00:00 2001
From: DemonExposer <kbdmns@gmail.com>
Date: Tue, 19 Jul 2022 16:49:37 +0200
Subject: [PATCH] Return statements are now not allowed outside of functions
 (mostly)

---
 Tokens/Operators/N-Ary/MultilineStatementOperator.cs | 11 +++++++++--
 Types/Function/FunctionBody.cs                       |  4 +++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Tokens/Operators/N-Ary/MultilineStatementOperator.cs b/Tokens/Operators/N-Ary/MultilineStatementOperator.cs
index 8e8095e..5e96ca0 100644
--- a/Tokens/Operators/N-Ary/MultilineStatementOperator.cs
+++ b/Tokens/Operators/N-Ary/MultilineStatementOperator.cs
@@ -6,16 +6,23 @@
 namespace Interpreter.Tokens.Operators.N_Ary; 
 
 public class MultilineStatementOperator : NAryOperator {
+	public bool IsPartOfFunction = false;
+	
 	public MultilineStatementOperator() {
 		Symbol = "{}";
 	}
 
 	public override Object Evaluate(List<TrieDictionary<Object>> vars) {
 		foreach (Token t in Children) {
-			if (t is ReturnStatement) // TODO: add flag to check if this is part of a function
+			if (t is ReturnStatement) {
+				if (!IsPartOfFunction)
+					throw new FormatException("Line " + t.Line + ": return statement not allowed outside of function");
+				
 				return t.Evaluate(vars);
+			}
 
-			if (t is BinaryStatement) {
+			if (t is BinaryStatement bs) {
+				((MultilineStatementOperator) bs.Right).IsPartOfFunction = IsPartOfFunction;
 				Object obj = t.Evaluate(vars);
 				if (obj != null!)
 					return obj;
diff --git a/Types/Function/FunctionBody.cs b/Types/Function/FunctionBody.cs
index 6cf564b..b5812ef 100644
--- a/Types/Function/FunctionBody.cs
+++ b/Types/Function/FunctionBody.cs
@@ -4,10 +4,12 @@
 namespace Interpreter.Types.Function; 
 
 public class FunctionBody {
-	public MultilineStatementOperator expressions;
+	public MultilineStatementOperator expressions = null!;
 
 	public FunctionBody(MultilineStatementOperator expressions) {
 		this.expressions = expressions;
+		if (this.expressions != null!)
+			this.expressions.IsPartOfFunction = true;
 	}
 
 	public virtual Object Execute(Object[] args, TrieDictionary<Object> vars, List<TrieDictionary<Object>> topScopeVars) => expressions.Evaluate(new List<TrieDictionary<Object>> {topScopeVars[0], vars});