...

compiler/Compiler/Diagnostic.cs

@@ -0,0 +1,154 @@
+namespace Compiler;
+
+public sealed class Diagnostic(DiagnosticSeverity severity, string message, string? help, FileInfo? file)
+{
+    public static DiagnosticBuilder Info(string message) => new DiagnosticBuilder(DiagnosticSeverity.Info, message);
+    public static DiagnosticBuilder Warning(string message) => new DiagnosticBuilder(DiagnosticSeverity.Warning, message);
+    public static DiagnosticBuilder Error(string message) => new DiagnosticBuilder(DiagnosticSeverity.Error, message);
+
+    public readonly DiagnosticSeverity Severity = severity;
+    public readonly string Message = message;
+    public readonly string? Help = help;
+    public readonly FileInfo? File = file;
+}
+
+public sealed class DiagnosticBuilder(DiagnosticSeverity severity, string message)
+{
+    private FileInfo? file;
+    private string? help;
+
+    public DiagnosticBuilder At(string fileName, int line, int column, int length)
+    {
+        file = new FileInfo(fileName, line, column, length);
+        return this;
+    }
+
+    public DiagnosticBuilder At(string fileName, Token? token)
+    {
+        if (token != null)
+        {
+            At(fileName, token.Line, token.Column, token.Length);
+        }
+
+        return this;
+    }
+
+    public DiagnosticBuilder At(string fileName, Node? node)
+    {
+        if (node != null && node.Tokens.Count != 0)
+        {
+            // todo(nub31): Calculate length based on last token
+            At(fileName, node.Tokens[0]);
+        }
+
+        return this;
+    }
+
+    public DiagnosticBuilder WithHelp(string helpMessage)
+    {
+        help = helpMessage;
+        return this;
+    }
+
+    public Diagnostic Build()
+    {
+        return new Diagnostic(severity, message, help, file);
+    }
+}
+
+public sealed class FileInfo(string file, int line, int column, int length)
+{
+    public readonly string File = file;
+    public readonly int Line = line;
+    public readonly int Column = column;
+    public readonly int Length = length;
+}
+
+public enum DiagnosticSeverity
+{
+    Info,
+    Warning,
+    Error,
+}
+
+public sealed class CompileException(Diagnostic diagnostic) : Exception
+{
+    public readonly Diagnostic Diagnostic = diagnostic;
+}
+
+public static class DiagnosticFormatter
+{
+    public static void Print(Diagnostic diagnostic, TextWriter writer)
+    {
+        var (label, color) = diagnostic.Severity switch
+        {
+            DiagnosticSeverity.Info => ("info", Ansi.Cyan),
+            DiagnosticSeverity.Warning => ("warning", Ansi.Yellow),
+            DiagnosticSeverity.Error => ("error", Ansi.Red),
+            _ => ("unknown", Ansi.Reset),
+        };
+
+        writer.Write(color);
+        writer.Write(label);
+        writer.Write(Ansi.Reset);
+        writer.Write(": ");
+        writer.WriteLine(diagnostic.Message);
+
+        if (diagnostic.File is null)
+            return;
+
+        var file = diagnostic.File;
+        var lineNumberWidth = diagnostic.File.Line.ToString().Length;
+
+        writer.WriteLine($" {new string(' ', lineNumberWidth)}{file.File}:{file.Line}:{file.Column}");
+        writer.WriteLine($"{new string(' ', lineNumberWidth)} | ");
+
+        var sourceLine = TryReadLine(file.File, file.Line);
+        if (sourceLine != null)
+        {
+            writer.Write($"{file.Line.ToString().PadLeft(lineNumberWidth)} | ");
+            writer.WriteLine(sourceLine);
+
+            writer.Write(new string(' ', lineNumberWidth));
+            writer.Write(" | ");
+            writer.Write(new string(' ', file.Column - 1));
+            writer.Write(color);
+            writer.Write(new string('^', Math.Max(1, file.Length)));
+            writer.WriteLine(Ansi.Reset);
+        }
+
+        writer.WriteLine($"{new string(' ', lineNumberWidth)} |");
+
+        if (!string.IsNullOrWhiteSpace(diagnostic.Help))
+        {
+            writer.WriteLine($"   = help: {diagnostic.Help}");
+        }
+    }
+
+    private static string? TryReadLine(string file, int line)
+    {
+        try
+        {
+            using var reader = new StreamReader(file);
+            for (var i = 1; i < line; i++)
+            {
+                if (reader.ReadLine() == null)
+                    return null;
+            }
+
+            return reader.ReadLine();
+        }
+        catch
+        {
+            return null;
+        }
+    }
+
+    private static class Ansi
+    {
+        public const string Reset = "\e[0m";
+        public const string Red = "\e[31m";
+        public const string Yellow = "\e[33m";
+        public const string Cyan = "\e[36m";
+    }
+}

compiler/Compiler/Generator.cs

@@ -185,10 +185,11 @@ public sealed class Generator(List<NodeDefinition> nodes)
         return node switch
         {
             NodeExpressionBinary expression => EmitExpressionBinary(expression),
+            NodeExpressionUnary expression => EmitExpressionUnary(expression),
             NodeExpressionBoolLiteral expression => expression.Value.Value ? "true" : "false",
             NodeExpressionIntLiteral expression => expression.Value.Value.ToString(),
             NodeExpressionStringLiteral expression => $"(struct string){{ \"{expression.Value.Value}\", {expression.Value.Value.Length} }}",
-            NodeExpressionStructLiteral expression => EmitStructLiteral(expression),
+            NodeExpressionStructLiteral expression => EmitExpressionStructLiteral(expression),
             NodeExpressionMemberAccess expression => EmitExpressionMemberAccess(expression),
             NodeExpressionIdent expression => expression.Value.Ident,
             _ => throw new ArgumentOutOfRangeException(nameof(node), node, null)
@@ -221,23 +222,19 @@ public sealed class Generator(List<NodeDefinition> nodes)
         };
     }
 
-    private static string CType(NodeType node, string? varName = null)
+    private string EmitExpressionUnary(NodeExpressionUnary expression)
     {
-        return node switch
+        var target = EmitExpression(expression.Target);
+
+        return expression.Operation switch
         {
-            NodeTypeVoid => "void" + (varName != null ? $" {varName}" : ""),
+            NodeExpressionUnary.Op.Negate => $"(-{target})",
-            NodeTypeBool => "bool" + (varName != null ? $" {varName}" : ""),
+            NodeExpressionUnary.Op.Invert => $"(!{target})",
-            NodeTypeCustom type => $"struct {type.Name.Ident}" + (varName != null ? $" {varName}" : ""),
+            _ => throw new ArgumentOutOfRangeException()
-            NodeTypeSInt type => $"int{type.Width}_t" + (varName != null ? $" {varName}" : ""),
-            NodeTypeUInt type => $"uint{type.Width}_t" + (varName != null ? $" {varName}" : ""),
-            NodeTypePointer type => CType(type.To) + (varName != null ? $" *{varName}" : "*"),
-            NodeTypeString => "struct string" + (varName != null ? $" {varName}" : ""),
-            NodeTypeFunc type => $"{CType(type.ReturnType)} (*{varName})({string.Join(", ", type.Parameters.Select(p => CType(p)))})",
-            _ => throw new ArgumentOutOfRangeException(nameof(node), node, null)
         };
     }
 
-    private string EmitStructLiteral(NodeExpressionStructLiteral expression)
+    private string EmitExpressionStructLiteral(NodeExpressionStructLiteral expression)
     {
         var initializerValues = new Dictionary<string, string>();
 
@@ -257,6 +254,22 @@ public sealed class Generator(List<NodeDefinition> nodes)
         var target = EmitExpression(expression.Target);
         return $"{target}.{expression.Name.Ident}";
     }
+
+    private static string CType(NodeType node, string? varName = null)
+    {
+        return node switch
+        {
+            NodeTypeVoid => "void" + (varName != null ? $" {varName}" : ""),
+            NodeTypeBool => "bool" + (varName != null ? $" {varName}" : ""),
+            NodeTypeCustom type => $"struct {type.Name.Ident}" + (varName != null ? $" {varName}" : ""),
+            NodeTypeSInt type => $"int{type.Width}_t" + (varName != null ? $" {varName}" : ""),
+            NodeTypeUInt type => $"uint{type.Width}_t" + (varName != null ? $" {varName}" : ""),
+            NodeTypePointer type => CType(type.To) + (varName != null ? $" *{varName}" : "*"),
+            NodeTypeString => "struct string" + (varName != null ? $" {varName}" : ""),
+            NodeTypeFunc type => $"{CType(type.ReturnType)} (*{varName})({string.Join(", ", type.Parameters.Select(p => CType(p)))})",
+            _ => throw new ArgumentOutOfRangeException(nameof(node), node, null)
+        };
+    }
 }
 
 internal class IndentedTextWriter

compiler/Compiler/Parser.cs

@@ -2,21 +2,31 @@
 
 namespace Compiler;
 
-public sealed class Parser(List<Token> tokens)
+public sealed class Parser(string fileName, List<Token> tokens)
 {
-    public static List<NodeDefinition> Parse(List<Token> tokens)
+    public static List<NodeDefinition> Parse(string fileName, List<Token> tokens, out List<Diagnostic> diagnostics)
     {
-        return new Parser(tokens).Parse();
+        return new Parser(fileName, tokens).Parse(out diagnostics);
     }
 
     private int index;
 
-    private List<NodeDefinition> Parse()
+    private List<NodeDefinition> Parse(out List<Diagnostic> diagnostics)
     {
         var nodes = new List<NodeDefinition>();
+        diagnostics = [];
 
+        try
+        {
             while (Peek() != null)
+            {
                 nodes.Add(ParseDefinition());
+            }
+        }
+        catch (CompileException e)
+        {
+            diagnostics.Add(e.Diagnostic);
+        }
 
         return nodes;
     }
@@ -66,7 +76,7 @@ public sealed class Parser(List<Token> tokens)
             return new NodeDefinitionStruct(TokensFrom(startIndex), name, fields);
         }
 
-        throw new Exception("Not a valid definition");
+        throw new CompileException(Diagnostic.Error("Not a valid definition").At(fileName, Peek()).Build());
     }
 
     private NodeStatement ParseStatement()
@@ -135,7 +145,7 @@ public sealed class Parser(List<Token> tokens)
             return new NodeStatementAssignment(TokensFrom(startIndex), target, value);
         }
 
-        throw new Exception("Not a valid followup for expression statement");
+        throw new CompileException(Diagnostic.Error("Cannot use expression in statement context unless called as a function or used in assignment").At(fileName, target).Build());
     }
 
     private NodeExpression ParseExpression(int minPrecedence = -1)
@@ -198,6 +208,16 @@ public sealed class Parser(List<Token> tokens)
             ExpectSymbol(Symbol.CloseParen);
             expr = value;
         }
+        else if (TryExpectSymbol(Symbol.Minus))
+        {
+            var target = ParseExpression();
+            expr = new NodeExpressionUnary(TokensFrom(startIndex), target, NodeExpressionUnary.Op.Negate);
+        }
+        else if (TryExpectSymbol(Symbol.Bang))
+        {
+            var target = ParseExpression();
+            expr = new NodeExpressionUnary(TokensFrom(startIndex), target, NodeExpressionUnary.Op.Invert);
+        }
         else if (TryExpectIntLiteral(out var intLiteral))
         {
             expr = new NodeExpressionIntLiteral(TokensFrom(startIndex), intLiteral);
@@ -233,7 +253,7 @@ public sealed class Parser(List<Token> tokens)
         }
         else
         {
-            throw new Exception("Not a valid expression leaf");
+            throw new CompileException(Diagnostic.Error("Expected start of expression").At(fileName, Peek()).Build());
         }
 
         if (TryExpectSymbol(Symbol.Period))
@@ -302,7 +322,7 @@ public sealed class Parser(List<Token> tokens)
             }
         }
 
-        throw new Exception("Not a valid type");
+        throw new CompileException(Diagnostic.Error("Expected type").At(fileName, Peek()).Build());
     }
 
     private List<Token> TokensFrom(int startIndex)
@@ -329,7 +349,7 @@ public sealed class Parser(List<Token> tokens)
             return;
         }
 
-        throw new Exception($"Expected symbol '{symbol}'");
+        throw new CompileException(Diagnostic.Error($"Expected '{symbol.AsString()}'").At(fileName, Peek()).Build());
     }
 
     private bool TryExpectSymbol(Symbol symbol)
@@ -351,7 +371,7 @@ public sealed class Parser(List<Token> tokens)
             return token;
         }
 
-        throw new Exception("Expected ident");
+        throw new CompileException(Diagnostic.Error("Expected identifier").At(fileName, Peek()).Build());
     }
 
     private bool TryExpectIdent([NotNullWhen(true)] out TokenIdent? ident)
@@ -409,7 +429,7 @@ public sealed class Parser(List<Token> tokens)
     private Token Consume()
     {
         if (index >= tokens.Count)
-            throw new Exception("End of tokens");
+            throw new CompileException(Diagnostic.Error("Unexpected end of tokens").At(fileName, Peek()).Build());
 
         return tokens[index++];
     }
@@ -607,7 +627,6 @@ public sealed class NodeExpressionBinary(List<Token> tokens, NodeExpression left
     public readonly Op Operation = operation;
     public readonly NodeExpression Right = right;
 
-
     public enum Op
     {
         Add,
@@ -635,6 +654,18 @@ public sealed class NodeExpressionBinary(List<Token> tokens, NodeExpression left
     }
 }
 
+public sealed class NodeExpressionUnary(List<Token> tokens, NodeExpression target, NodeExpressionUnary.Op op) : NodeExpression(tokens)
+{
+    public NodeExpression Target { get; } = target;
+    public Op Operation { get; } = op;
+
+    public enum Op
+    {
+        Negate,
+        Invert,
+    }
+}
+
 public abstract class NodeType(List<Token> tokens) : Node(tokens);
 
 public sealed class NodeTypeVoid(List<Token> tokens) : NodeType(tokens);

compiler/Compiler/Program.cs

@@ -1,42 +1,33 @@
 using Compiler;
 
-const string contents = """
+var file = File.ReadAllText("test.nub");
-                        struct person {
+
-                            age: i32
+var tokens = Tokenizer.Tokenize("test.nub", file, out var tokenizerDiagnostics);
-                            name: string
+
+foreach (var diagnostic in tokenizerDiagnostics)
+{
+    DiagnosticFormatter.Print(diagnostic, Console.Error);
 }
 
-                        func main(): i32 {
+if (tokenizerDiagnostics.Any(x => x.Severity == DiagnosticSeverity.Error))
-                            let x: i32 = 23
+{
-                            x = 24
+    return 1;
-                            
-                            if true {
-                                x = 49
-                            } else {
-                                x = 3
 }
 
-                            let i: i32 = 0
+var nodes = Parser.Parse("test.nub", tokens, out var parserDiagnostics);
 
-                            x = 1 + 2 * 34
+foreach (var diagnostic in parserDiagnostics)
-                            
+{
-                            while i < 10 {
+    DiagnosticFormatter.Print(diagnostic, Console.Error);
-                                i = i + 1
-                                x = i
 }
 
-                            let me: person = struct person { age = 21 name = "Oliver" }
+if (parserDiagnostics.Any(x => x.Severity == DiagnosticSeverity.Error))
-                            
+{
-                            do_something(me.name)
+    return 1;
-                            return x
 }
 
-                        func do_something(text: string): void {
-                        }
-                        """;
-
-var tokens = Tokenizer.Tokenize(contents);
-var nodes = Parser.Parse(tokens);
 var output = Generator.Emit(nodes);
 
 File.WriteAllText("C:/Users/oliste/repos/nub-lang/compiler/Compiler/out.c", output);
+
+return 0;

compiler/Compiler/Tokenizer.cs

@@ -3,21 +3,23 @@ using System.Text;
 
 namespace Compiler;
 
-public sealed class Tokenizer(string contents)
+public sealed class Tokenizer(string fileName, string contents)
 {
-    public static List<Token> Tokenize(string contents)
+    public static List<Token> Tokenize(string fileName, string contents, out List<Diagnostic> diagnostics)
     {
-        return new Tokenizer(contents).Tokenize();
+        return new Tokenizer(fileName, contents).Tokenize(out diagnostics);
     }
 
     private int index;
     private int line = 1;
     private int column = 1;
 
-    private List<Token> Tokenize()
+    private List<Token> Tokenize(out List<Diagnostic> diagnostics)
     {
         var tokens = new List<Token>();
-
+        diagnostics = [];
+        try
+        {
             while (true)
             {
                 if (!TryPeek(out var c))
@@ -31,6 +33,11 @@ public sealed class Tokenizer(string contents)
 
                 tokens.Add(ParseToken());
             }
+        }
+        catch (CompileException e)
+        {
+            diagnostics.Add(e.Diagnostic);
+        }
 
         return tokens;
     }
@@ -347,7 +354,7 @@ public sealed class Tokenizer(string contents)
     private char Consume()
     {
         if (index >= contents.Length)
-            throw new Exception("End of tokens");
+            throw new CompileException(Diagnostic.Error("Unexpected end of file").At(fileName, line, column, 0).Build());
 
         var c = contents[index];
 
@@ -470,3 +477,61 @@ public sealed class TokenKeyword(int line, int column, int length, Keyword keywo
 {
     public readonly Keyword Keyword = keyword;
 }
+
+public static class TokenExtensions
+{
+    public static string AsString(this Symbol symbol)
+    {
+        return symbol switch
+        {
+            Symbol.OpenCurly => "{",
+            Symbol.CloseCurly => "}",
+            Symbol.OpenParen => "(",
+            Symbol.CloseParen => ")",
+            Symbol.Comma => ",",
+            Symbol.Period => ",",
+            Symbol.Colon => ":",
+            Symbol.Caret => "^",
+            Symbol.Bang => "!",
+            Symbol.Equal => "=",
+            Symbol.EqualEqual => "==",
+            Symbol.BangEqual => "!+",
+            Symbol.LessThan => "<",
+            Symbol.LessThanLessThan => "<<",
+            Symbol.LessThanEqual => "<=",
+            Symbol.GreaterThan => ">",
+            Symbol.GreaterThanGreaterThan => ">>",
+            Symbol.GreaterThanEqual => ">=",
+            Symbol.Plus => "+",
+            Symbol.PlusEqual => "+=",
+            Symbol.Minus => "-",
+            Symbol.MinusEqual => "-=",
+            Symbol.Star => "*",
+            Symbol.StarEqual => "*=",
+            Symbol.ForwardSlash => "/",
+            Symbol.ForwardSlashEqual => "/=",
+            Symbol.Percent => "%",
+            Symbol.PercentEqual => "%=",
+            Symbol.Ampersand => "&",
+            Symbol.AmpersandAmpersand => "&&",
+            Symbol.Pipe => "|",
+            Symbol.PipePipe => "||",
+            _ => throw new ArgumentOutOfRangeException(nameof(symbol), symbol, null)
+        };
+    }
+
+    public static string AsString(this Keyword symbol)
+    {
+        return symbol switch
+        {
+            Keyword.Func => "func",
+            Keyword.Struct => "struct",
+            Keyword.Let => "let",
+            Keyword.If => "if",
+            Keyword.Else => "else",
+            Keyword.While => "while",
+            Keyword.Return => "return",
+            _ => throw new ArgumentOutOfRangeException(nameof(symbol), symbol, null)
+        };
+    }
+}

compiler/Compiler/test.nub

@@ -0,0 +1,33 @@
+struct person {
+    age: i32
+    name: string
+}
+
+func main(): i32 {
+    let x: i32 = 23
+    x = 24
+    
+    if !true {
+        x = 49
+        return x
+    } else {
+        x = 3
+    }
+    
+    let i: i32 = 0
+    
+    x = 1 + 2 * 34
+    
+    while i < 10 {
+        i = i + 1
+        x = i
+    }
+    
+    let me: person = struct person { age = 21 name = "Oliver" }
+    
+    do_something(me.name)
+    return x
+}
+
+func do_something(text: string): void {
+}