Tests for Parser

Src/AST/Myc.Ast.Compiler.Binder.pas

@@ -16,6 +16,9 @@ uses
     Myc.Ast;
 
 type
+    // Exception specific to the binding phase (e.g. undefined symbols, invalid identifiers)
+    EBinderException = class(EAstException);
+
     IAstBinder = interface(IAstVisitor)
         function Execute(const RootNode: IAstNode; out Layout: IScopeLayout): IAstNode;
     end;
@@ -236,7 +239,7 @@ begin
     if Node.Address.Kind = akUnresolved then
     begin
         if not ResolveSymbol(Node.Name, physAddr) then
-            raise Exception.CreateFmt('Undefined identifier: "%s"', [Node.Name]);
+            raise EBinderException.CreateFmt('Undefined identifier: "%s"', [Node.Name]);
 
         if physAddr.ScopeDepth > 0 then
         begin
@@ -262,7 +265,7 @@ var
 begin
     var identifier := Node.Target.AsIdentifier;
     if not IsValidIdentifier(identifier.Name) then
-        raise Exception.CreateFmt('Invalid identifier name: "%s".', [identifier.Name]);
+        raise EBinderException.CreateFmt('Invalid identifier name: "%s".', [identifier.Name]);
 
     slot := FCurrentBuilder.Define(identifier.Name);
     addr := TResolvedAddress.Create(akLocalOrParent, 0, slot);

Src/AST/Myc.Ast.Compiler.TypeChecker.pas

@@ -15,6 +15,9 @@ uses
     Myc.Ast;
 
 type
+    // Exception for type mismatches during compilation
+    ETypeCheckException = class(EAstException);
+
     IAstTypeChecker = interface(IAstVisitor)
         function Execute(const RootNode: IAstNode; const Layout: IScopeLayout): IAstNode;
     end;
@@ -110,7 +113,8 @@ begin
             for i := 1 to Address.ScopeDepth do
             begin
                 if not Assigned(ctx.FParent) then
-                    raise Exception.CreateFmt('Scope depth mismatch during type lookup. Requested Depth: %d.', [Address.ScopeDepth]);
+                    raise ETypeCheckException
+                        .CreateFmt('Scope depth mismatch during type lookup. Requested Depth: %d.', [Address.ScopeDepth]);
                 ctx := ctx.FParent;
             end;
 
@@ -318,10 +322,10 @@ begin
         if (targetType.Kind = stUnknown) then
         begin
             if not TTypeRules.CanAssign(sourceType, targetType) then
-                raise ETypeException.CreateFmt('Cannot assign type %s to %s', [sourceType.ToString, targetType.ToString]);
+                raise ETypeCheckException.CreateFmt('Cannot assign type %s to %s', [sourceType.ToString, targetType.ToString]);
         end
         else
-            raise ETypeException.CreateFmt('Cannot assign type %s to %s', [sourceType.ToString, targetType.ToString]);
+            raise ETypeCheckException.CreateFmt('Cannot assign type %s to %s', [sourceType.ToString, targetType.ToString]);
     end;
 
     if ((targetType.Kind = stUnknown) or Assigned(placeholderType)) and (sourceType.Kind <> stUnknown) then
@@ -466,13 +470,13 @@ begin
                 var argsStr: string := '';
                 for i := 0 to High(argTypes) do
                     argsStr := argsStr + argTypes[i].ToString + ' ';
-                raise ETypeException
+                raise ETypeCheckException
                     .CreateFmt('No matching signature for call with args (%s) found on method %s', [argsStr, calleeType.ToString]);
             end;
         end;
     end
     else if calleeType.Kind <> TStaticTypeKind.stUnknown then
-        raise ETypeException.CreateFmt('Cannot invoke type %s as a function.', [calleeType.ToString]);
+        raise ETypeCheckException.CreateFmt('Cannot invoke type %s as a function.', [calleeType.ToString]);
 
     Result := TAst.FunctionCall(newCallee, newArgs, retType, Node.IsTailCall);
 end;
@@ -509,14 +513,19 @@ begin
     if (conditionType.Kind <> stUnknown)
         and not TTypeRules.CanAssign(TTypes.Ordinal, conditionType)
         and not TTypeRules.CanAssign(TTypes.Boolean, conditionType) then
-        raise ETypeException.CreateFmt('If condition must be Boolean or Ordinal, but got %s', [conditionType.ToString]);
+        raise ETypeCheckException.CreateFmt('If condition must be Boolean or Ordinal, but got %s', [conditionType.ToString]);
 
     thenType := newThen.AsTypedNode.StaticType;
     elseType :=
         if newElse <> nil then newElse.AsTypedNode.StaticType
         else TTypes.Void;
 
-    resultType := TTypeRules.Promote(thenType, elseType);
+    try
+        resultType := TTypeRules.Promote(thenType, elseType);
+    except
+        on E: Exception do // Catch base exception (ETypeException from Myc.Ast.Types)
+            raise ETypeCheckException.Create(E.Message);
+    end;
 
     Result := TAst.IfExpr(newCond, newThen, newElse, resultType);
 end;
@@ -534,12 +543,17 @@ begin
     if (conditionType.Kind <> stUnknown)
         and not TTypeRules.CanAssign(TTypes.Ordinal, conditionType)
         and not TTypeRules.CanAssign(TTypes.Boolean, conditionType) then
-        raise ETypeException.CreateFmt('Ternary condition must be Boolean or Ordinal, but got %s', [conditionType.ToString]);
+        raise ETypeCheckException.CreateFmt('Ternary condition must be Boolean or Ordinal, but got %s', [conditionType.ToString]);
 
     thenType := newThen.AsTypedNode.StaticType;
     elseType := newElse.AsTypedNode.StaticType;
 
-    resultType := TTypeRules.Promote(thenType, elseType);
+    try
+        resultType := TTypeRules.Promote(thenType, elseType);
+    except
+        on E: Exception do
+            raise ETypeCheckException.Create(E.Message);
+    end;
 
     Result := TAst.TernaryExpr(newCond, newThen, newElse, resultType);
 end;
@@ -562,7 +576,7 @@ begin
         begin
             fieldIndex := baseType.Definition.IndexOf(Node.Member.Value);
             if fieldIndex < 0 then
-                raise ETypeException.CreateFmt('Member "%s" not found in type %s', [Node.Member.Value.Name, baseType.ToString]);
+                raise ETypeCheckException.CreateFmt('Member "%s" not found in type %s', [Node.Member.Value.Name, baseType.ToString]);
 
             var fieldType := TTypes.FromScalarKind(baseType.Definition.Fields[fieldIndex].Value);
 
@@ -576,11 +590,11 @@ begin
             var genDef := baseType.GenericDefinition;
             fieldIndex := genDef.IndexOf(Node.Member.Value);
             if fieldIndex < 0 then
-                raise ETypeException.CreateFmt('Member "%s" not found in type %s', [Node.Member.Value.Name, baseType.ToString]);
+                raise ETypeCheckException.CreateFmt('Member "%s" not found in type %s', [Node.Member.Value.Name, baseType.ToString]);
             elemType := genDef.Fields[fieldIndex].Value;
         end
         else
-            raise ETypeException.CreateFmt('Member access requires a record type, but got %s', [baseType.ToString]);
+            raise ETypeCheckException.CreateFmt('Member access requires a record type, but got %s', [baseType.ToString]);
     end;
 
     Result := TAst.MemberAccess(newBase, newMember.AsKeyword, elemType);
@@ -601,10 +615,10 @@ begin
     if (baseType.Kind <> TStaticTypeKind.stUnknown) then
     begin
         if (baseType.Kind <> TStaticTypeKind.stSeries) and (baseType.Kind <> TStaticTypeKind.stRecordSeries) then
-            raise ETypeException.CreateFmt('Indexer `[]` can only be applied to series types, but got %s', [baseType.ToString]);
+            raise ETypeCheckException.CreateFmt('Indexer `[]` can only be applied to series types, but got %s', [baseType.ToString]);
 
         if (indexType.Kind <> stUnknown) and not TTypeRules.CanAssign(TTypes.Ordinal, indexType) then
-            raise ETypeException.CreateFmt('Indexer `[]` requires an Ordinal index, but got %s', [indexType.ToString]);
+            raise ETypeCheckException.CreateFmt('Indexer `[]` requires an Ordinal index, but got %s', [indexType.ToString]);
 
         if baseType.Kind = TStaticTypeKind.stSeries then
             elemType := baseType.ElementType
@@ -708,10 +722,10 @@ begin
     if (seriesType.Kind <> stUnknown) then
     begin
         if (seriesType.Kind <> TStaticTypeKind.stSeries) then
-            raise ETypeException.CreateFmt('"add" requires a series as its first argument, but got %s', [seriesType.ToString]);
+            raise ETypeCheckException.CreateFmt('"add" requires a series as its first argument, but got %s', [seriesType.ToString]);
 
         if not TTypeRules.CanAssign(seriesType.ElementType, valueType) then
-            raise ETypeException
+            raise ETypeCheckException
                 .CreateFmt('Cannot add item of type %s to series of type %s', [valueType.ToString, seriesType.ElementType.ToString]);
     end;
 
@@ -719,7 +733,7 @@ begin
     begin
         var lookbackType := newLookback.AsTypedNode.StaticType;
         if (lookbackType.Kind <> stUnknown) and not (lookbackType.Kind = TStaticTypeKind.stOrdinal) then
-            raise ETypeException.Create('Lookback parameter for "add" must be an ordinal value.');
+            raise ETypeCheckException.Create('Lookback parameter for "add" must be an ordinal value.');
     end;
 
     Result := TAst.AddSeriesItem(newSeries.AsIdentifier, newValue, newLookback, TTypes.Void);
@@ -741,7 +755,7 @@ begin
     if (seriesType.Kind <> stUnknown)
         and (seriesType.Kind <> TStaticTypeKind.stSeries)
         and (seriesType.Kind <> TStaticTypeKind.stRecordSeries) then
-        raise ETypeException.CreateFmt('"length" requires a series, but got %s', [seriesType.ToString]);
+        raise ETypeCheckException.CreateFmt('"length" requires a series, but got %s', [seriesType.ToString]);
 
     Result := TAst.SeriesLength(newSeries.AsIdentifier, TTypes.Ordinal);
 end;

Src/AST/Myc.Ast.Evaluator.pas

@@ -12,6 +12,9 @@ uses
     Myc.Ast.Scope;
 
 type
+    // Exception for runtime errors during script evaluation
+    EEvaluatorException = class(EAstException);
+
     // The standard AST evaluator for production use.
     // This class inherits directly from TInterfacedObject as it is an
     // Interpreter (AST -> TDataValue), not a Transformer (AST -> IAstNode).
@@ -222,7 +225,7 @@ begin
             adr: TResolvedAddress;
         begin
             if (Length(ArgValues) <> Length(params)) then
-                raise EArgumentException.CreateFmt('Argument count mismatch: expected %d, got %d', [Length(params), Length(ArgValues)]);
+                raise EEvaluatorException.CreateFmt('Argument count mismatch: expected %d, got %d', [Length(params), Length(ArgValues)]);
 
             // Create the new execution scope for this function call.
             lambdaScope := TScope.CreateScope(closureScope, descriptor, capturedCells);
@@ -265,17 +268,17 @@ end;
 
 function TEvaluatorVisitor.VisitQuasiquote(const Node: IQuasiquoteNode): TDataValue;
 begin
-    raise Exception.Create('Quasiquote nodes are a compile-time construct and cannot be evaluated at runtime.');
+    raise EEvaluatorException.Create('Quasiquote nodes are a compile-time construct and cannot be evaluated at runtime.');
 end;
 
 function TEvaluatorVisitor.VisitUnquote(const Node: IUnquoteNode): TDataValue;
 begin
-    raise Exception.Create('Unquote nodes are a compile-time construct and cannot be evaluated at runtime.');
+    raise EEvaluatorException.Create('Unquote nodes are a compile-time construct and cannot be evaluated at runtime.');
 end;
 
 function TEvaluatorVisitor.VisitUnquoteSplicing(const Node: IUnquoteSplicingNode): TDataValue;
 begin
-    raise Exception.Create('Unquote-splicing nodes are a compile-time construct and cannot be evaluated at runtime.');
+    raise EEvaluatorException.Create('Unquote-splicing nodes are a compile-time construct and cannot be evaluated at runtime.');
 end;
 
 function TEvaluatorVisitor.VisitFunctionCall(const Node: IFunctionCallNode): TDataValue;
@@ -308,7 +311,7 @@ begin
         // --- Dynamic Path (Default) ---
         calleeValue := Node.Callee.Accept(Self);
         if calleeValue.Kind <> vkMethod then
-            raise EArgumentException.Create('Expression is not invokable in this context.');
+            raise EEvaluatorException.Create('Expression is not invokable in this context.');
 
         argNodes := Node.Arguments;
         SetLength(argValues, Length(argNodes));
@@ -371,7 +374,7 @@ begin
     begin
         lookbackValue := Node.Lookback.Accept(Self);
         if (lookbackValue.Kind <> vkScalar) or (lookbackValue.AsScalar.Kind <> TScalar.TKind.Ordinal) then
-            raise EArgumentException.Create('Lookback parameter must be an integer.');
+            raise EEvaluatorException.Create('Lookback parameter must be an integer.');
         lookback := lookbackValue.AsScalar.Value.AsInt64;
     end;
 
@@ -379,7 +382,7 @@ begin
         vkRecordSeries:
         begin
             if (itemValue.Kind <> vkRecord) then
-                raise EArgumentException.Create('Can only add record values to a TScalarRecordSeries.');
+                raise EEvaluatorException.Create('Can only add record values to a TScalarRecordSeries.');
 
             with seriesVar.AsRecordSeries do
             begin
@@ -387,7 +390,7 @@ begin
             end;
         end;
     else
-        raise EArgumentException.Create('"add" operation is only supported for series types.');
+        raise EEvaluatorException.Create('"add" operation is only supported for series types.');
     end;
     Result := TDataValue.Void;
 end;
@@ -395,7 +398,7 @@ end;
 function TEvaluatorVisitor.VisitAssignment(const Node: IAssignmentNode): TDataValue;
 begin
     if Node.Target.Kind <> akIdentifier then
-        raise ETypeException.Create('Runtime Error: Assignment target must be an identifier.');
+        raise EEvaluatorException.Create('Runtime Error: Assignment target must be an identifier.');
 
     // Evaluate value
     Result := Node.Value.Accept(Self);
@@ -423,7 +426,7 @@ begin
     begin
         var recordDef := TRttiAstHelper.JsonToRecordDefinition(def);
         if Length(recordDef.Fields) = 0 then
-            raise EArgumentException.Create('Failed to parse record definition from JSON array.');
+            raise EEvaluatorException.Create('Failed to parse record definition from JSON array.');
         var recordSeries := TScalarRecordSeries.Create(recordDef);
         Result := TDataValue.FromRecordSeries(recordSeries);
     end
@@ -457,7 +460,7 @@ begin
     indexValue := Node.Index.Accept(Self);
 
     if (indexValue.Kind <> vkScalar) or (indexValue.AsScalar.Kind <> TScalar.TKind.Ordinal) then
-        raise EArgumentException.Create('Indexer `[]` requires an integer argument.');
+        raise EEvaluatorException.Create('Indexer `[]` requires an integer argument.');
 
     index := indexValue.AsScalar.Value.AsInt64;
 
@@ -466,14 +469,15 @@ begin
         begin
             series := baseValue.AsSeries;
             if (index < 0) or (index >= series.TotalCount) then
-                raise EArgumentException.CreateFmt('Index %d is out of bounds for series with %d elements.', [index, series.TotalCount]);
+                raise EEvaluatorException.CreateFmt('Index %d is out of bounds for series with %d elements.', [index, series.TotalCount]);
             Result := TDataValue(series.Items[Integer(index)]); // Explicit cast
         end;
         vkRecordSeries:
         begin
             recSeries := baseValue.AsRecordSeries;
             if (index < 0) or (index >= recSeries.TotalCount) then
-                raise EArgumentException.CreateFmt('Index %d is out of bounds for series with %d elements.', [index, recSeries.TotalCount]);
+                raise EEvaluatorException
+                    .CreateFmt('Index %d is out of bounds for series with %d elements.', [index, recSeries.TotalCount]);
 
             // Materialize the TScalarRecord by accessing each member series by index
             fieldCount := Length(recSeries.Def.Fields);
@@ -491,7 +495,7 @@ begin
             Result := TDataValue.FromRecord(rec);
         end;
     else
-        raise EArgumentException.Create('Indexer `[]` is not supported for this value type.');
+        raise EEvaluatorException.Create('Indexer `[]` is not supported for this value type.');
     end;
 end;
 
@@ -511,12 +515,12 @@ begin
             var rec := baseValue.AsGenericRecord;
             var fieldIndex := rec.IndexOf(Node.Member.Value);
             if fieldIndex < 0 then
-                raise EArgumentException.CreateFmt('Member ":%s" not found in record.', [Node.Member.Value.Name]);
+                raise EEvaluatorException.CreateFmt('Member ":%s" not found in record.', [Node.Member.Value.Name]);
 
             Result := rec.Fields[fieldIndex].Value;
         end;
     else
-        raise EArgumentException.Create('Member access operator `.` is not supported for this value type.');
+        raise EEvaluatorException.Create('Member access operator `.` is not supported for this value type.');
     end;
 end;
 
@@ -559,7 +563,7 @@ begin
         Result := TDataValue.FromRecord(rec);
     end
     else
-        raise EInvalidOpException.Create('RecordLiteral has no definition (Binder/TypeChecker failure).');
+        raise EEvaluatorException.Create('RecordLiteral has no definition (Binder/TypeChecker failure).');
 end;
 
 function TEvaluatorVisitor.VisitVariableDeclaration(const Node: IVariableDeclarationNode): TDataValue;
@@ -567,7 +571,7 @@ var
     address: TResolvedAddress;
 begin
     if Node.Target.Kind <> akIdentifier then
-        raise ETypeException.Create('Runtime Error: Variable declaration target must be an identifier.');
+        raise EEvaluatorException.Create('Runtime Error: Variable declaration target must be an identifier.');
 
     // 1. Evaluate Initializer
     if Assigned(Node.Initializer) then
@@ -635,7 +639,8 @@ begin
         vkSeries: len := seriesValue.AsSeries.Count;
         vkRecordSeries: len := seriesValue.AsRecordSeries.Count;
     else
-        raise EArgumentException.CreateFmt('Cannot get length of type %s.', [GetEnumName(TypeInfo(TDataValueKind), Ord(seriesValue.Kind))]);
+        raise EEvaluatorException
+            .CreateFmt('Cannot get length of type %s.', [GetEnumName(TypeInfo(TDataValueKind), Ord(seriesValue.Kind))]);
     end;
 
     Result := TDataValue(TScalar.FromInt64(len)); // Explicit cast

Src/AST/Myc.Ast.Nodes.pas

@@ -401,6 +401,10 @@ type
     // A factory for creating visitors
     TEvaluatorFactory = reference to function(const Scope: IExecutionScope): IEvaluatorVisitor;
 
+    // Base class for ALL compiler exceptions.
+    // Renamed from IAstException to EAstException to follow standard Delphi naming convention.
+    EAstException = class(Exception);
+
 implementation
 
 uses

Src/AST/Myc.Ast.Script.pas

@@ -7,10 +7,21 @@ uses
     Myc.Ast.Nodes,
     Myc.Ast.Visitor;
 
+type
+    // Exception for parsing errors containing location information
+    EParserException = class(EAstException)
+    strict private
+        FLine: Integer;
+        FCol: Integer;
+    public
+        constructor Create(const AMessage: string; ALine, ACol: Integer);
+        property Line: Integer read FLine;
+        property Col: Integer read FCol;
+    end;
+
 var
     // This BNF should always be kept up to date and valid. It is used to comunicate with LLMs.
     // (Nop isn't part of the language syntax.)
-
     BNF: String =
         '''
         (* ---------------------------------------------------------------------- *)
@@ -46,7 +57,7 @@ var
         list            ::= "(" list_content ")"
 
         (* The parser distinguishes between special forms (like 'if') and
-           general function calls based on the first element. *)
+            general function calls based on the first element. *)
         list_content    ::= special_form | function_call
 
         special_form    ::= "if" expression expression expression?
@@ -61,7 +72,7 @@ var
                           | dot_identifier expression
 
         (* A function call is any list not recognized as a special form.
-           The first 'expression' is the callee, the rest are the arguments. *)
+            The first 'expression' is the callee, the rest are the arguments. *)
         function_call   ::= expression expression*
 
         (* ---------------------------------------------------------------------- *)
@@ -86,7 +97,7 @@ var
         dot_identifier  ::= "." identifier
 
         (* An identifier is a sequence of characters that are not delimiters.
-           The lexer is very permissive. *)
+            The lexer is very permissive. *)
         identifier      ::= ? any sequence of chars not containing whitespace, '()[]{}'`~:; ?
 
         digit           ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
@@ -142,20 +153,29 @@ type
     TToken = record
         Kind: TTokenKind;
         Text: string;
+        Line: Integer;
+        Col: Integer;
     end;
 
     TLexer = class
     private
         FSource: string;
         FCurrentPos: Integer;
+        FLine: Integer;
+        FLineStart: Integer;
         function Peek: Char;
         procedure Advance;
         function ReadNumber: string;
         function ReadString: string;
         function ReadIdentifier: string;
+        function GetCurrentLine: Integer;
+        function GetCurrentCol: Integer;
+        procedure Error(const Msg: string);
     public
         constructor Create(const ASource: string);
         function GetNextToken: TToken;
+        property CurrentLine: Integer read GetCurrentLine;
+        property CurrentCol: Integer read GetCurrentCol;
     end;
 
     TExpr = record
@@ -168,6 +188,8 @@ type
     private
         FLexer: TLexer;
         FCurrentToken: TToken;
+        procedure Error(const Msg: string);
+        procedure ErrorFmt(const Msg: string; const Args: array of const);
         procedure Consume(AExpectedKind: TTokenKind);
         procedure NextToken;
         function ParseList: IAstNode;
@@ -223,6 +245,15 @@ type
         procedure VisitNop(const Node: INopNode); override;
     end;
 
+{ EParserException }
+
+constructor EParserException.Create(const AMessage: string; ALine, ACol: Integer);
+begin
+    inherited CreateFmt('[Line %d, Col %d] %s', [ALine, ACol, AMessage]);
+    FLine := ALine;
+    FCol := ACol;
+end;
+
 { TLexer }
 
 constructor TLexer.Create(const ASource: string);
@@ -230,6 +261,23 @@ begin
     inherited Create;
     FSource := ASource;
     FCurrentPos := 1;
+    FLine := 1;
+    FLineStart := 1;
+end;
+
+function TLexer.GetCurrentLine: Integer;
+begin
+    Result := FLine;
+end;
+
+function TLexer.GetCurrentCol: Integer;
+begin
+    Result := FCurrentPos - FLineStart + 1;
+end;
+
+procedure TLexer.Error(const Msg: string);
+begin
+    raise EParserException.Create(Msg, FLine, GetCurrentCol);
 end;
 
 function TLexer.Peek: Char;
@@ -241,8 +289,19 @@ begin
 end;
 
 procedure TLexer.Advance;
+var
+    c: Char;
 begin
-    inc(FCurrentPos);
+    if FCurrentPos <= Length(FSource) then
+    begin
+        c := FSource[FCurrentPos];
+        if c = #10 then
+        begin
+            Inc(FLine);
+            FLineStart := FCurrentPos + 1;
+        end;
+    end;
+    Inc(FCurrentPos);
 end;
 
 function TLexer.ReadIdentifier: string;
@@ -293,7 +352,7 @@ begin
             begin
                 Advance; // Consume '\'
                 if FCurrentPos > Length(FSource) then
-                    raise Exception.Create('Syntax Error: String literal ends with an escape character.');
+                    Error('Syntax Error: String literal ends with an escape character.');
 
                 c := Peek; // Get escaped char
                 case c of
@@ -319,7 +378,7 @@ begin
         end;
 
         // If we fall out of the loop, we hit EOF without a closing quote.
-        raise Exception.Create('Syntax Error: Unterminated string literal.');
+        Error('Syntax Error: Unterminated string literal.');
 
     finally
         builder.Free;
@@ -349,6 +408,10 @@ begin
         break;
     end;
 
+    // Capture location for the start of the token
+    Result.Line := CurrentLine;
+    Result.Col := CurrentCol;
+
     if FCurrentPos > Length(FSource) then
     begin
         Result.Kind := tkEOF;
@@ -449,6 +512,16 @@ begin
     inherited;
 end;
 
+procedure TParser.Error(const Msg: string);
+begin
+    raise EParserException.Create(Msg, FCurrentToken.Line, FCurrentToken.Col);
+end;
+
+procedure TParser.ErrorFmt(const Msg: string; const Args: array of const);
+begin
+    raise EParserException.Create(Format(Msg, Args), FCurrentToken.Line, FCurrentToken.Col);
+end;
+
 procedure TParser.NextToken;
 begin
     FCurrentToken := FLexer.GetNextToken;
@@ -457,7 +530,7 @@ end;
 procedure TParser.Consume(AExpectedKind: TTokenKind);
 begin
     if FCurrentToken.Kind <> AExpectedKind then
-        raise Exception.CreateFmt('Syntax Error: Expected token %s, but found %s', [AExpectedKind.ToString, FCurrentToken.Kind.ToString]);
+        ErrorFmt('Syntax Error: Expected token %s, but found %s', [AExpectedKind.ToString, FCurrentToken.Kind.ToString]);
     NextToken;
 end;
 
@@ -471,9 +544,9 @@ begin
         while FCurrentToken.Kind <> tkRightBracket do
         begin
             if FCurrentToken.Kind = tkEOF then
-                raise Exception.Create('Syntax Error: Unexpected end of file.');
+                Error('Syntax Error: Unexpected end of file.');
             if FCurrentToken.Kind <> tkIdentifier then
-                raise Exception.Create('Syntax Error: Expected identifier in parameter list.');
+                Error('Syntax Error: Expected identifier in parameter list.');
             params.Add(TAst.Identifier(FCurrentToken.Text));
             NextToken;
         end;
@@ -496,17 +569,17 @@ begin
         while FCurrentToken.Kind <> tkRightBrace do
         begin
             if FCurrentToken.Kind = tkEOF then
-                raise Exception.Create('Syntax Error: Unexpected end of file in record literal.');
+                Error('Syntax Error: Unexpected end of file in record literal.');
 
             // Key must be a keyword
             if FCurrentToken.Kind <> tkKeyword then
-                raise Exception.Create('Syntax Error: Expected keyword (e.g., :key) as field name in record literal.');
+                Error('Syntax Error: Expected keyword (e.g., :key) as field name in record literal.');
             fieldName := FCurrentToken.Text;
             NextToken;
 
             // Value can be any expression
             if FCurrentToken.Kind = tkRightBrace then
-                raise Exception.Create('Syntax Error: Missing value for key ' + fieldName + ' in record literal.');
+                Error('Syntax Error: Missing value for key ' + fieldName + ' in record literal.');
             fieldValue := ParseExpression.Node;
 
             fields.Add(TRecordFieldLiteral.Create(TAst.Keyword(fieldName), fieldValue));
@@ -520,7 +593,6 @@ begin
 end;
 
 function TParser.ParseList: IAstNode;
-
 var
     elements: TList<TExpr>;
     head: TExpr;
@@ -530,14 +602,14 @@ var
 begin
     Consume(tkLeftParen);
     if FCurrentToken.Kind = tkRightParen then
-        raise Exception.Create('Syntax Error: Empty list () is not a valid expression.');
+        Error('Syntax Error: Empty list () is not a valid expression.');
 
     elements := TList<TExpr>.Create;
     try
         while FCurrentToken.Kind <> tkRightParen do
         begin
             if FCurrentToken.Kind = tkEOF then
-                raise Exception.Create('Syntax Error: Unexpected end of file.');
+                Error('Syntax Error: Unexpected end of file.');
             elements.Add(ParseExpression);
         end;
 
@@ -557,7 +629,7 @@ begin
             if SameText(head.Token.Text, 'if') then
             begin
                 if not (Length(tailNodes) in [2, 3]) then
-                    raise Exception.Create('Syntax Error in if statement.');
+                    Error('Syntax Error in if statement.');
 
                 var elseBranch: IAstNode := nil;
                 if Length(tailNodes) = 3 then
@@ -568,7 +640,7 @@ begin
             else if SameText(head.Token.Text, '?') then
             begin
                 if Length(tailNodes) <> 3 then
-                    raise Exception.Create('Syntax Error in ternary statement.');
+                    Error('Syntax Error in ternary statement.');
 
                 Result := TAst.TernaryExpr(tailNodes[0], tailNodes[1], tailNodes[2]);
             end
@@ -576,7 +648,7 @@ begin
             begin
                 // Identifier check removed to support macros (e.g. def ~x 1)
                 if not (Length(tailNodes) in [1, 2]) then
-                    raise Exception.CreateFmt('Syntax Error: ''def'' requires a target and an optional initializer.', []);
+                    Error('Syntax Error: ''def'' requires a target and an optional initializer.');
 
                 initializer := nil;
                 if Length(tailNodes) = 2 then
@@ -587,13 +659,13 @@ begin
             else if SameText(head.Token.Text, 'defmacro') then
             begin
                 if (Length(tailNodes) <> 3) or (tailTokens[0].Kind <> tkIdentifier) then
-                    raise Exception.Create('Syntax Error: ''defmacro'' requires a name, a parameter list, and a body.');
+                    Error('Syntax Error: ''defmacro'' requires a name, a parameter list, and a body.');
 
                 var macroName := tailNodes[0].AsIdentifier;
                 var macroParams := elements[2].Params;
 
                 if tailTokens[2].Kind <> tkBacktick then
-                    raise Exception.Create('Syntax Error: Expected a quasiquote as macro body.');
+                    Error('Syntax Error: Expected a quasiquote as macro body.');
 
                 var macroBody := IQuasiQuoteNode(tailNodes[2]);
 
@@ -603,14 +675,14 @@ begin
             begin
                 // Identifier check removed
                 if Length(tailNodes) <> 2 then
-                    raise Exception.Create('Syntax Error: ''assign'' requires exactly 2 arguments (target and value).');
+                    Error('Syntax Error: ''assign'' requires exactly 2 arguments (target and value).');
 
                 Result := TAst.Assign(tailNodes[0], tailNodes[1]);
             end
             else if SameText(head.Token.Text, 'fn') then
             begin
                 if Length(tailNodes) <> 2 then
-                    raise Exception.Create('Syntax Error: ''fn'' requires a parameter list and a body.');
+                    Error('Syntax Error: ''fn'' requires a parameter list and a body.');
                 Result := TAst.LambdaExpr(elements[1].Params, tailNodes[1]);
             end
             else if SameText(head.Token.Text, 'do') then
@@ -620,15 +692,16 @@ begin
             else if SameText(head.Token.Text, 'get') then
             begin
                 if Length(tailNodes) <> 2 then
-                    raise Exception.Create('Syntax Error: ''get'' requires exactly 2 arguments (base and index).');
+                    Error('Syntax Error: ''get'' requires exactly 2 arguments (base and index).');
                 Result := TAst.Indexer(tailNodes[0], tailNodes[1])
             end
             else if (Length(head.Token.Text) > 1) and (head.Token.Text.StartsWith('.')) then
             begin
                 if Length(tailNodes) <> 1 then
-                    raise Exception.CreateFmt(
+                    ErrorFmt(
                         'Syntax Error: Member access (e.g., ''%s'') requires exactly 1 argument (the base object).',
-                        [head.Token.Text]);
+                        [head.Token.Text]
+                    );
                 Result := TAst.MemberAccess(tailNodes[0], TAst.Keyword(head.Token.Text.Substring(1)));
             end;
         end;
@@ -696,7 +769,7 @@ begin
             else if TryStrToFloat(FCurrentToken.Text, dbl, TFormatSettings.Invariant) then
                 Result.Node := TAst.Constant(dbl)
             else
-                raise Exception.CreateFmt('Syntax Error: Invalid number format "%s"', [FCurrentToken.Text]);
+                ErrorFmt('Syntax Error: Invalid number format "%s"', [FCurrentToken.Text]);
             NextToken;
         end;
         tkString:
@@ -736,7 +809,7 @@ begin
         tkLeftBrace: Result.Node := ParseRecordLiteral;
         tkEOF: {nop};
     else
-        raise Exception.CreateFmt('Syntax Error: Unexpected token %s', [FCurrentToken.Kind.ToString]);
+        ErrorFmt('Syntax Error: Unexpected token %s', [FCurrentToken.Kind.ToString]);
     end;
 end;
 
@@ -744,7 +817,7 @@ function TParser.Parse: IAstNode;
 begin
     var expr := ParseExpression;
     if FCurrentToken.Kind <> tkEOF then
-        raise Exception.Create('Syntax Error: Unexpected characters after end of expression.');
+        Error('Syntax Error: Unexpected characters after end of expression.');
     Result := expr.Node;
 end;
 

Test/AST/Test.Myc.Ast.Script.pas

@@ -356,27 +356,27 @@ end;
 procedure TTestMycAstScript.Parser_Error_UnbalancedParens_MissingRight;
 begin
     // FIX 2: Pass explicit Exception type to WillRaise
-    Assert.WillRaise(procedure begin Parse('(a b'); end, Exception);
+    Assert.WillRaise(procedure begin Parse('(a b'); end, EParserException);
 end;
 
 procedure TTestMycAstScript.Parser_Error_UnbalancedParens_ExtraRight;
 begin
-    Assert.WillRaise(procedure begin Parse('a )'); end, Exception);
+    Assert.WillRaise(procedure begin Parse('a )'); end, EParserException);
 end;
 
 procedure TTestMycAstScript.Parser_Error_UnterminatedString;
 begin
-    Assert.WillRaise(procedure begin Parse('"hello'); end, Exception);
+    Assert.WillRaise(procedure begin Parse('"hello'); end, EParserException);
 end;
 
 procedure TTestMycAstScript.Parser_Error_EmptyList;
 begin
-    Assert.WillRaise(procedure begin Parse('()'); end, Exception);
+    Assert.WillRaise(procedure begin Parse('()'); end, EParserException);
 end;
 
 procedure TTestMycAstScript.Parser_Error_Record_MissingValue;
 begin
-    Assert.WillRaise(procedure begin Parse('{:a 1 :b}'); end, Exception);
+    Assert.WillRaise(procedure begin Parse('{:a 1 :b}'); end, EParserException);
 end;
 
 end.