diff --git a/src/Diagnostics/DiagnosticCode.hpp b/src/Diagnostics/DiagnosticCode.hpp
index f7a161b..87b7a52 100644
--- a/src/Diagnostics/DiagnosticCode.hpp
+++ b/src/Diagnostics/DiagnosticCode.hpp
@@ -4,6 +4,7 @@
 
 enum class DiagnosticCode{
     UnexpectedCharacter,
+    UnexpectedToken,
 };
 
 #endif //PORYGONLANG_DIAGNOSTICCODE_HPP
diff --git a/src/Parser/ParsedExpressions/ParsedExpression.hpp b/src/Parser/ParsedExpressions/ParsedExpression.hpp
index 9a1d71b..f72b054 100644
--- a/src/Parser/ParsedExpressions/ParsedExpression.hpp
+++ b/src/Parser/ParsedExpressions/ParsedExpression.hpp
@@ -7,6 +7,8 @@
 #include "../BinaryOperatorKind.hpp"
 
 enum class ParsedExpressionKind{
+    Bad,
+
     LiteralInteger,
     LiteralFloat,
     LiteralString,
@@ -40,6 +42,15 @@ public:
     }
 };
 
+class BadExpression : public ParsedExpression{
+public:
+    BadExpression(unsigned int position, unsigned int length) : ParsedExpression(position, length){}
+
+    ParsedExpressionKind GetKind() final{
+        return ParsedExpressionKind::Bad;
+    }
+};
+
 class LiteralIntegerExpression : public ParsedExpression{
     long _value;
 public:
diff --git a/src/Parser/Parser.cpp b/src/Parser/Parser.cpp
index da83350..83a3006 100644
--- a/src/Parser/Parser.cpp
+++ b/src/Parser/Parser.cpp
@@ -7,24 +7,24 @@
 ParsedScriptStatement* Parser::Parse() {
     vector<ParsedStatement*> statements;
     while (true){
-        auto next = Parser::Next();
+        auto next = this -> Next();
         if (next->GetKind() == TokenKind::EndOfFile){
             break;
         }
         if (next->GetKind() == TokenKind::WhiteSpace){
             continue;
         }
-        statements.push_back(Parser::ParseStatement(next));
+        statements.push_back(this -> ParseStatement(next));
     }
     return new ParsedScriptStatement(statements);
 }
 
 ParsedStatement* Parser::ParseStatement(IToken* current){
-    return new ParsedExpressionStatement(Parser::ParseExpression(current));
+    return new ParsedExpressionStatement(this -> ParseExpression(current));
 }
 
 ParsedExpression* Parser::ParseExpression(IToken* current){
-    return Parser::ParseBinaryExpression(current, OperatorPrecedence::No);
+    return this -> ParseBinaryExpression(current, OperatorPrecedence::No);
 }
 
 
@@ -44,7 +44,7 @@ UnaryOperatorKind GetUnaryOperatorKind(TokenKind kind){
         case TokenKind::PlusToken: return UnaryOperatorKind::Identity;
         case TokenKind::MinusToken: return UnaryOperatorKind::Negation;
         case TokenKind::NotKeyword: return UnaryOperatorKind::LogicalNegation;
-        default:
+        default: // This should never trigger, so throw.
             throw;
     }
 }
@@ -58,7 +58,7 @@ BinaryOperatorKind GetBinaryOperatorKind(TokenKind kind){
         case TokenKind::EqualityToken: return BinaryOperatorKind ::Equality;
         case TokenKind::AndKeyword: return BinaryOperatorKind ::LogicalAnd;
         case TokenKind::OrKeyword: return BinaryOperatorKind ::LogicalOr;
-        default:
+        default: // This should never trigger, so throw.
             throw;
     }
 }
@@ -82,22 +82,22 @@ ParsedExpression* Parser::ParseBinaryExpression(IToken* current, OperatorPrecede
     ParsedExpression* left;
     if (unaryPrecedence != OperatorPrecedence::No && unaryPrecedence >= parentPrecedence){
         UnaryOperatorKind operatorKind = GetUnaryOperatorKind(current -> GetKind());
-        auto next = Parser::Next();
-        auto operand = Parser::ParseBinaryExpression(next, unaryPrecedence);
+        auto next = this -> Next();
+        auto operand = this -> ParseBinaryExpression(next, unaryPrecedence);
         auto startPos = current -> GetStartPosition();
         left = new UnaryExpression(operatorKind, operand, startPos, operand -> GetEndPosition() - startPos);
     } else{
-        left = Parser::ParsePrimaryExpression(current);
+        left = this -> ParsePrimaryExpression(current);
     }
     while (true){
-        auto next  = Parser::Peek();
+        auto next  = this -> Peek();
         OperatorPrecedence binaryPrecedence = GetBinaryPrecedence(next -> GetKind());
         if (binaryPrecedence == OperatorPrecedence::No || binaryPrecedence <= parentPrecedence){
             break;
         }
         auto operatorKind = GetBinaryOperatorKind(next -> GetKind());
-        Parser::Next();
-        auto right = ParseBinaryExpression(Parser::Next(), binaryPrecedence);
+        this -> Next();
+        auto right = ParseBinaryExpression(this -> Next(), binaryPrecedence);
         auto startPos = left -> GetStartPosition();
         left = new BinaryExpression(operatorKind, left, right, startPos, right -> GetEndPosition() - startPos);
     }
@@ -111,18 +111,19 @@ ParsedExpression *Parser::ParsePrimaryExpression(IToken *current) {
         case TokenKind ::TrueKeyword: return new LiteralBoolExpression(current);
         case TokenKind ::FalseKeyword: return new LiteralBoolExpression(current);
         default:
-            throw;
+            this -> ScriptData -> Diagnostics.LogError(DiagnosticCode::UnexpectedToken, current->GetStartPosition(), current->GetLength());
+            return new BadExpression(current->GetStartPosition(), current->GetLength());
     }
 }
 
 
 IToken *Parser::Peek() {
-    return Parser::_tokens[_position];
+    return this -> _tokens[_position];
 }
 
 IToken *Parser::Next() {
-    Parser::_position++;
-    return Parser::_tokens[_position - 1];
+    this -> _position++;
+    return this -> _tokens[_position - 1];
 }
 
 #ifdef TESTS_BUILD
@@ -130,7 +131,7 @@ IToken *Parser::Next() {
 
 TEST_CASE( "Parse single true keyword", "[parser]" ) {
     vector<IToken*> v {new SimpleToken(TokenKind::TrueKeyword,0,0), new SimpleToken(TokenKind::EndOfFile,0,0)};
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
@@ -143,7 +144,7 @@ TEST_CASE( "Parse single true keyword", "[parser]" ) {
 
 TEST_CASE( "Parse single false keyword", "[parser]" ) {
     vector<IToken*> v {new SimpleToken(TokenKind::FalseKeyword,0,0), new SimpleToken(TokenKind::EndOfFile,0,0)};
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
@@ -161,7 +162,7 @@ TEST_CASE( "Parse simple addition", "[parser]" ) {
         new IntegerToken(10, 0, 0),
         new SimpleToken(TokenKind::EndOfFile,0,0)
     };
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
@@ -184,7 +185,7 @@ TEST_CASE( "Parse simple negation", "[parser]" ) {
             new IntegerToken(10, 0, 0),
             new SimpleToken(TokenKind::EndOfFile,0,0)
     };
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
@@ -204,7 +205,7 @@ TEST_CASE( "Parse logical negation", "[parser]" ) {
             new SimpleToken(TokenKind::FalseKeyword,0,0),
             new SimpleToken(TokenKind::EndOfFile,0,0)
     };
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
@@ -227,7 +228,7 @@ TEST_CASE( "Assert binary precedence", "[parser]" ) {
             new IntegerToken(6, 0, 0),
             new SimpleToken(TokenKind::EndOfFile,0,0)
     };
-    Parser parser = Parser(v);
+    Parser parser = Parser(v, nullptr);
     auto parsedStatements = parser.Parse() -> GetStatements();
     REQUIRE(parsedStatements.size() == 1);
     auto firstStatement = parsedStatements[0];
diff --git a/src/Parser/Parser.hpp b/src/Parser/Parser.hpp
index 5d8290d..cb8c8d1 100644
--- a/src/Parser/Parser.hpp
+++ b/src/Parser/Parser.hpp
@@ -5,6 +5,7 @@
 
 
 #include "ParsedStatements/ParsedStatement.hpp"
+#include "../Script.hpp"
 
 enum class OperatorPrecedence {
     No,
@@ -19,6 +20,7 @@ enum class OperatorPrecedence {
 class Parser {
     vector<IToken*> _tokens;
     unsigned int _position;
+    Script* ScriptData;
 
     IToken* Peek();
     IToken* Next();
@@ -28,9 +30,10 @@ class Parser {
     ParsedExpression* ParsePrimaryExpression(IToken* current);
 public:
     ParsedScriptStatement* Parse();
-    explicit Parser(vector<IToken*> tokens){
+    explicit Parser(vector<IToken*> tokens, Script* scriptData){
         _tokens = std::move(tokens);
         _position = 0;
+        ScriptData = scriptData;
     }
 };
 
diff --git a/src/Script.cpp b/src/Script.cpp
index b888f80..01eb0c8 100644
--- a/src/Script.cpp
+++ b/src/Script.cpp
@@ -14,7 +14,7 @@ Script Script::Create(string script) {
 void Script::Parse(string script) {
     auto lexer = Lexer(std::move(script), this);
     auto lexResult = lexer.Lex();
-    auto parser = Parser(lexResult);
+    auto parser = Parser(lexResult, this);
     auto parseResult = parser.Parse();
     for (auto token : lexResult){
         delete token;