diff --git a/include/AST/AST.h b/include/AST/AST.h
index 3c5d02d..6a34ee7 100644
--- a/include/AST/AST.h
+++ b/include/AST/AST.h
@@ -363,9 +363,9 @@ class Declaration : public ExternalDeclaration, public Statement {
 class VariableDeclaration : public Declaration {
 
 public:
-  VariableDeclaration(std::unique_ptr<Type> type, const std::string &name,
+  VariableDeclaration(SourceLocation location, std::unique_ptr<Type> type, const std::string &name,
                       std::unique_ptr<Expression> initializerExpr)
-      : type(std::move(type)), identifierName(name),
+      : ASTNode(location), type(std::move(type)), identifierName(name),
         initializerExpr(std::move(initializerExpr)) {}
 
   const std::string &getIdentifierName() const { return identifierName; }
@@ -400,14 +400,17 @@ class VariableDeclarationList : public Declaration {
   std::vector<std::unique_ptr<VariableDeclaration>> declarations;
 };
 
-class ParameterDeclaration {
+class ParameterDeclaration : public ASTNode {
 
 public:
-  ParameterDeclaration(const std::string &name, std::unique_ptr<Type> type)
-      : name(name), type(std::move(type)) {}
+  ParameterDeclaration(SourceLocation location, const std::string &name, std::unique_ptr<Type> type)
+      : ASTNode(location), name(name), type(std::move(type)) {}
 
   const std::string &getName() { return name; }
   Type *getType() { return type.get(); }
+  void accept(ASTVisitor *visitor) override {
+  
+  }
 
 private:
   std::string name;
diff --git a/lib/AST/PrinterASTVisitor.cpp b/lib/AST/PrinterASTVisitor.cpp
index 3ab68de..27f1a8f 100644
--- a/lib/AST/PrinterASTVisitor.cpp
+++ b/lib/AST/PrinterASTVisitor.cpp
@@ -54,7 +54,7 @@ void PrinterASTVisitor::visit(VariableDeclarationList *varDeclList) {
 
 void PrinterASTVisitor::visit(VariableDeclaration *varDecl) {
   auto typeName = varDecl->getType() != nullptr ? varDecl->getType()->toString() : "";
-  print("|-VariableDeclaration: name=" + varDecl->getIdentifierName() + ((typeName != "") ? (", type=" + typeName) : ""));
+  print("|-VariableDeclaration: name=" + varDecl->getIdentifierName() + ((typeName != "") ? (", type=" + typeName) : "") + loc(varDecl->getSourceLocation()));
 
   indent();
   if (auto exp = varDecl->getInitialzerExpression()) {
@@ -276,7 +276,7 @@ void PrinterASTVisitor::visit(FunctionDeclaration *funcDecl) {
   indent();
 
   for (auto &arg : funcDecl->getParams()) {
-    print("name=" + arg->getName() + ", type=" + arg->getType()->toString());
+    print("name=" + arg->getName() + ", type=" + arg->getType()->toString() + loc(arg->getSourceLocation()));
   }
 
   resetIndent();
@@ -299,7 +299,12 @@ void PrinterASTVisitor::visit(CaseLabel *caseLabel) {
 
 std::string PrinterASTVisitor::loc(const SourceLocation &sourceLoc) {
   std::stringstream ssLoc;
-  ssLoc << "[line: " << sourceLoc.startLine << ", col:" << sourceLoc.startCol << "]->" << "[line: " << sourceLoc.endLine << ", col:" << sourceLoc.endCol << "]";
+  if (sourceLoc.startLine == sourceLoc.endLine) {
+    ssLoc << "[line: " << sourceLoc.startLine << ", col:" << sourceLoc.startCol << " -> " << "col:" << sourceLoc.endCol << "]";
+  } else {
+    ssLoc << "[line: " << sourceLoc.startLine << ", col:" << sourceLoc.startCol << "] -> " << "[line: " << sourceLoc.endLine << ", col:" << sourceLoc.endCol << "]";
+  }
+
   return ssLoc.str();
 }
 
diff --git a/lib/Parser/Parser.cpp b/lib/Parser/Parser.cpp
index 47b7e1d..7f3ebfb 100644
--- a/lib/Parser/Parser.cpp
+++ b/lib/Parser/Parser.cpp
@@ -92,24 +92,28 @@ std::unique_ptr<FunctionDeclaration> Parser::parseFunctionDeclaration() {
 
 std::unique_ptr<Declaration> Parser::parseDeclaration() {
   if (auto type = parseType()) {
+    SourceLocation startLoc = curToken->getSourceLocation();
     advanceToken();
 
     // Only type, no variable name
     if (curToken->is(TokenKind::semiColon)) {
       advanceToken();
-      return std::make_unique<VariableDeclaration>(std::move(type),
+      return std::make_unique<VariableDeclaration>(startLoc, std::move(type),
                                                    std::string(), nullptr);
     }
 
     const std::string &name = curToken->getIdentifierName();
-
+    SourceLocation endLoc = curToken->getSourceLocation();
     advanceToken();
 
     // Type and variable name, no initializer expression
     if (curToken->is(TokenKind::semiColon)) {
       advanceToken();
-      return std::make_unique<VariableDeclaration>(std::move(type), name,
-                                                   nullptr);
+      return std::make_unique<VariableDeclaration>(
+        SourceLocation(startLoc.startLine, startLoc.startCol, endLoc.startLine, endLoc.endCol), 
+        std::move(type), 
+        name,
+        nullptr);
     } else if (curToken->is(TokenKind::assign)) {
       // Initializer expression
       advanceToken();
@@ -124,7 +128,7 @@ std::unique_ptr<Declaration> Parser::parseDeclaration() {
         return declarations;
       } else if (curToken->is(TokenKind::semiColon)) {
         advanceToken();
-        return std::make_unique<VariableDeclaration>(std::move(type), name,
+        return std::make_unique<VariableDeclaration>(SourceLocation(), std::move(type), name,
                                                      std::move(exp));
       } else {
         reportError(ParserErrorKind::UnexpectedToken, "Parser error: unexpected token '" + curToken->getRawData() + "'");
@@ -147,13 +151,12 @@ std::unique_ptr<VariableDeclarationList> Parser::parseVariableDeclarationList(
     std::unique_ptr<Type> type, const std::string &identifierName,
     std::unique_ptr<Expression> initializerExpression) {
   std::vector<std::unique_ptr<VariableDeclaration>> declarations;
-  declarations.push_back(std::make_unique<VariableDeclaration>(
+  declarations.push_back(std::make_unique<VariableDeclaration>(SourceLocation(),
       nullptr, identifierName, std::move(initializerExpression)));
 
   do {
     advanceToken();
     if (!curToken->is(TokenKind::Identifier)) {
-      
       reportError(ParserErrorKind::ExpectedToken, "Parser error: expected identifier " + curToken->getRawData());
     }
 
@@ -170,10 +173,10 @@ std::unique_ptr<VariableDeclarationList> Parser::parseVariableDeclarationList(
         return nullptr;
       }
 
-      declarations.push_back(std::make_unique<VariableDeclaration>(
+      declarations.push_back(std::make_unique<VariableDeclaration>(SourceLocation(),
           nullptr, varName, std::move(exp)));
     } else {
-      declarations.push_back(std::make_unique<VariableDeclaration>(
+      declarations.push_back(std::make_unique<VariableDeclaration>(SourceLocation(),
           nullptr, varName, nullptr));
     }
   } while (curToken->is(TokenKind::comma));
@@ -679,11 +682,13 @@ Parser::parseFunctionParameters() {
     advanceToken();
 
     if (auto type = parseType()) {
+      SourceLocation startLoc = curToken->getSourceLocation();
       advanceToken();
 
       if (curToken->is(TokenKind::Identifier)) {
+        SourceLocation endLoc = curToken->getSourceLocation();
         auto param = std::make_unique<ParameterDeclaration>(
-            curToken->getIdentifierName(), std::move(type));
+          SourceLocation(startLoc.startLine, startLoc.startCol, endLoc.startLine, endLoc.endCol), curToken->getIdentifierName(), std::move(type));
         advanceToken();
         params.push_back(std::move(param));
       }