From 955869a3cf9bc96eb6755700bc2f885cf32eb04d Mon Sep 17 00:00:00 2001
From: nub31 <oliverlhs@outlook.com>
Date: Mon, 26 May 2025 19:16:56 +0200
Subject: [PATCH] ...

---
 build.sh                                      |  2 +-
 example/{c => interop}/bindings.nub           |  2 +
 example/program.nub                           |  7 +-
 .../Frontend/Diagnostics/Diagnostic.cs        | 18 ++--
 .../{SourceFile.cs => SourceText.cs}          | 11 +--
 .../Nub.Lang/Frontend/DiagnosticsResult.cs    |  2 +-
 .../Frontend/Lexing/DocumentationToken.cs     |  2 +-
 .../Frontend/Lexing/IdentifierToken.cs        |  2 +-
 .../Nub.Lang/Frontend/Lexing/Lexer.cs         | 33 +++----
 .../Nub.Lang/Frontend/Lexing/LiteralToken.cs  |  2 +-
 .../Nub.Lang/Frontend/Lexing/ModifierToken.cs |  2 +-
 .../Nub.Lang/Frontend/Lexing/SymbolToken.cs   |  5 +-
 .../Nub.Lang/Frontend/Lexing/Token.cs         |  4 +-
 .../Nub.Lang/Frontend/Parsing/ModuleNode.cs   | 10 --
 .../Nub.Lang/Frontend/Parsing/Parser.cs       | 51 +++++-----
 .../Nub.Lang/Frontend/Parsing/SourceFile.cs   |  8 ++
 .../Nub.Lang/Frontend/Typing/TypeChecker.cs   | 22 ++---
 src/compiler/Nub.Lang/Program.cs              | 97 ++++++-------------
 18 files changed, 124 insertions(+), 156 deletions(-)
 rename example/{c => interop}/bindings.nub (98%)
 rename src/compiler/Nub.Lang/Frontend/Diagnostics/{SourceFile.cs => SourceText.cs} (87%)
 delete mode 100644 src/compiler/Nub.Lang/Frontend/Parsing/ModuleNode.cs
 create mode 100644 src/compiler/Nub.Lang/Frontend/Parsing/SourceFile.cs

diff --git a/build.sh b/build.sh
index c4c6a61..9f2f60b 100755
--- a/build.sh
+++ b/build.sh
@@ -7,7 +7,7 @@ dotnet publish -c Release src/compiler/Nub.Lang
 
 clear
 
-nub example out/out.qbe
+nub example out/out.qbe > out/out.qbe
 
 nasm -g -felf64 src/runtime/runtime.asm -o out/runtime.o
 
diff --git a/example/c/bindings.nub b/example/interop/bindings.nub
similarity index 98%
rename from example/c/bindings.nub
rename to example/interop/bindings.nub
index e3fc6c4..e425923 100644
--- a/example/c/bindings.nub
+++ b/example/interop/bindings.nub
@@ -1,3 +1,5 @@
+module c_interop
+
 extern func printf(fmt: string, ...args: any)
 extern func getchar(): i32
 extern func puts(str: string)
diff --git a/example/program.nub b/example/program.nub
index 3ad47ba..3421d7f 100644
--- a/example/program.nub
+++ b/example/program.nub
@@ -1,12 +1,17 @@
-import c
+import c_interop
+
+module main
 
 /// # Documentation
 /// ## Documentation subtitle
 global func main(args: []string) {
     i = 0
+
     printf("%d\n", args.count)
+
     while i < args.count {
         printf("%s\n", args[i])
+
         i = i + 1
     }
 }
diff --git a/src/compiler/Nub.Lang/Frontend/Diagnostics/Diagnostic.cs b/src/compiler/Nub.Lang/Frontend/Diagnostics/Diagnostic.cs
index 0f547ac..1606084 100644
--- a/src/compiler/Nub.Lang/Frontend/Diagnostics/Diagnostic.cs
+++ b/src/compiler/Nub.Lang/Frontend/Diagnostics/Diagnostic.cs
@@ -17,7 +17,7 @@ public class Diagnostic
     {
         private readonly DiagnosticSeverity _severity;
         private readonly string _message;
-        private SourceFile? _sourceFile;
+        private SourceText? _sourceFile;
         private SourceSpan? _span;
         private string? _help;
 
@@ -29,7 +29,7 @@ public class Diagnostic
 
         public DiagnosticBuilder At(Token token)
         {
-            _sourceFile = token.SourceFile;
+            _sourceFile = token.SourceText;
             _span = SourceLocationCalculator.GetSpan(token);
             return this;
         }
@@ -41,14 +41,14 @@ public class Diagnostic
                 throw new ArgumentException("Node has no tokens", nameof(node));
             }
 
-            _sourceFile = node.Tokens[0].SourceFile;
+            _sourceFile = node.Tokens[0].SourceText;
             _span = SourceLocationCalculator.GetSpan(node);
             return this;
         }
 
-        public DiagnosticBuilder At(SourceFile sourceFile, SourceSpan span)
+        public DiagnosticBuilder At(SourceText sourceText, SourceSpan span)
         {
-            _sourceFile = sourceFile;
+            _sourceFile = sourceText;
             _span = span;
             return this;
         }
@@ -68,11 +68,11 @@ public class Diagnostic
 
     public DiagnosticSeverity Severity { get; }
     public string Message { get; }
-    public SourceFile? SourceFile { get; }
+    public SourceText? SourceFile { get; }
     public SourceSpan? Span { get; }
     public string? Help { get; }
 
-    private Diagnostic(DiagnosticSeverity severity, string message, SourceFile? sourceFile, SourceSpan? span, string? help)
+    private Diagnostic(DiagnosticSeverity severity, string message, SourceText? sourceFile, SourceSpan? span, string? help)
     {
         Severity = severity;
         Message = message;
@@ -123,9 +123,9 @@ public class Diagnostic
         };
     }
 
-    private static void AppendSourceContext(StringBuilder sb, SourceFile sourceFile, SourceSpan span)
+    private static void AppendSourceContext(StringBuilder sb, SourceText sourceText, SourceSpan span)
     {
-        var lines = sourceFile.Content.Split('\n');
+        var lines = sourceText.Content.Split('\n');
         var startLine = span.Start.Line;
         var endLine = span.End.Line;
 
diff --git a/src/compiler/Nub.Lang/Frontend/Diagnostics/SourceFile.cs b/src/compiler/Nub.Lang/Frontend/Diagnostics/SourceText.cs
similarity index 87%
rename from src/compiler/Nub.Lang/Frontend/Diagnostics/SourceFile.cs
rename to src/compiler/Nub.Lang/Frontend/Diagnostics/SourceText.cs
index 8a7ce89..c41b2f9 100644
--- a/src/compiler/Nub.Lang/Frontend/Diagnostics/SourceFile.cs
+++ b/src/compiler/Nub.Lang/Frontend/Diagnostics/SourceText.cs
@@ -1,10 +1,9 @@
-using System.Diagnostics.CodeAnalysis;
 using Nub.Lang.Frontend.Lexing;
 using Nub.Lang.Frontend.Parsing;
 
 namespace Nub.Lang.Frontend.Diagnostics;
 
-public readonly struct SourceFile(string path, string content)
+public readonly struct SourceText(string path, string content)
 {
     public string Path { get; } = path;
     public string Content { get; } = content;
@@ -80,8 +79,8 @@ public static class SourceLocationCalculator
 
     public static SourceSpan GetSpan(Token token)
     {
-        var start = IndexToLocation(token.SourceFile.Content, token.StartIndex);
-        var end = IndexToLocation(token.SourceFile.Content, token.EndIndex);
+        var start = IndexToLocation(token.SourceText.Content, token.StartIndex);
+        var end = IndexToLocation(token.SourceText.Content, token.EndIndex);
         return new SourceSpan(start, end);
     }
 
@@ -95,8 +94,8 @@ public static class SourceLocationCalculator
         var firstToken = node.Tokens[0];
         var lastToken = node.Tokens[^1];
 
-        var start = IndexToLocation(firstToken.SourceFile.Content, firstToken.StartIndex);
-        var end = IndexToLocation(lastToken.SourceFile.Content, lastToken.EndIndex);
+        var start = IndexToLocation(firstToken.SourceText.Content, firstToken.StartIndex);
+        var end = IndexToLocation(lastToken.SourceText.Content, lastToken.EndIndex);
 
         return new SourceSpan(start, end);
     }
diff --git a/src/compiler/Nub.Lang/Frontend/DiagnosticsResult.cs b/src/compiler/Nub.Lang/Frontend/DiagnosticsResult.cs
index d657d93..8805626 100644
--- a/src/compiler/Nub.Lang/Frontend/DiagnosticsResult.cs
+++ b/src/compiler/Nub.Lang/Frontend/DiagnosticsResult.cs
@@ -10,7 +10,7 @@ public class DiagnosticsResult(List<Diagnostic> diagnostics)
     {
         foreach (var diagnostic in diagnostics)
         {
-            Console.WriteLine(diagnostic.Format());
+            Console.Error.WriteLine(diagnostic.Format());
         }
     }
 }
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/DocumentationToken.cs b/src/compiler/Nub.Lang/Frontend/Lexing/DocumentationToken.cs
index d1f60f8..1dcbe3f 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/DocumentationToken.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/DocumentationToken.cs
@@ -2,7 +2,7 @@ using Nub.Lang.Frontend.Diagnostics;
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public class DocumentationToken(SourceFile sourceFile, int startIndex, int endIndex, string documentation) : Token(sourceFile, startIndex, endIndex)
+public class DocumentationToken(SourceText sourceText, int startIndex, int endIndex, string documentation) : Token(sourceText, startIndex, endIndex)
 {
     public string Documentation { get; } = documentation;
 }
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/IdentifierToken.cs b/src/compiler/Nub.Lang/Frontend/Lexing/IdentifierToken.cs
index b84520d..5494f72 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/IdentifierToken.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/IdentifierToken.cs
@@ -2,7 +2,7 @@
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public class IdentifierToken(SourceFile sourceFile, int startIndex, int endIndex, string value) : Token(sourceFile, startIndex, endIndex)
+public class IdentifierToken(SourceText sourceText, int startIndex, int endIndex, string value) : Token(sourceText, startIndex, endIndex)
 {
     public string Value { get; } = value;
 }
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs b/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
index af772d8..d080409 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
@@ -8,6 +8,7 @@ public class Lexer
     {
         ["func"] = Symbol.Func,
         ["import"] = Symbol.Import,
+        ["module"] = Symbol.Module,
         ["if"] = Symbol.If,
         ["else"] = Symbol.Else,
         ["while"] = Symbol.While,
@@ -56,14 +57,12 @@ public class Lexer
         ['&'] = Symbol.Ampersand,
     };
 
-    private string _src = null!;
-    private SourceFile _sourceFile;
+    private SourceText _sourceText;
     private int _index;
     
-    public List<Token> Lex(string src, SourceFile sourceFile)
+    public DiagnosticsResult<List<Token>> Tokenize(SourceText sourceText)
     {
-        _src = src;
-        _sourceFile = sourceFile;
+        _sourceText = sourceText;
         _index = 0;
         
         List<Token> tokens = [];
@@ -72,7 +71,7 @@ public class Lexer
             tokens.Add(token);
         }
 
-        return tokens;
+        return new DiagnosticsResult<List<Token>>([], tokens);
     }
 
     private void ConsumeWhitespace()
@@ -123,7 +122,7 @@ public class Lexer
 
         if (documentation != null)
         {
-            return new DocumentationToken(_sourceFile, startIndex, _index, documentation);
+            return new DocumentationToken(_sourceText, startIndex, _index, documentation);
         }
 
         ConsumeWhitespace();
@@ -146,20 +145,20 @@ public class Lexer
 
             if (Keywords.TryGetValue(buffer, out var keywordSymbol))
             {
-                return new SymbolToken(_sourceFile, startIndex, _index, keywordSymbol);
+                return new SymbolToken(_sourceText, startIndex, _index, keywordSymbol);
             }
 
             if (Modifiers.TryGetValue(buffer, out var modifer))
             {
-                return new ModifierToken(_sourceFile, startIndex, _index, modifer);
+                return new ModifierToken(_sourceText, startIndex, _index, modifer);
             }
 
             if (buffer is "true" or "false")
             {
-                return new LiteralToken(_sourceFile, startIndex, _index, NubPrimitiveType.Bool, buffer);
+                return new LiteralToken(_sourceText, startIndex, _index, NubPrimitiveType.Bool, buffer);
             }
 
-            return new IdentifierToken(_sourceFile, startIndex, _index, buffer);
+            return new IdentifierToken(_sourceText, startIndex, _index, buffer);
         }
 
         if (char.IsDigit(current))
@@ -197,7 +196,7 @@ public class Lexer
                 }
             }
 
-            return new LiteralToken(_sourceFile, startIndex, _index, isFloat ? NubPrimitiveType.F64 : NubPrimitiveType.I64, buffer);
+            return new LiteralToken(_sourceText, startIndex, _index, isFloat ? NubPrimitiveType.F64 : NubPrimitiveType.I64, buffer);
         }
 
         // TODO: Revisit this
@@ -217,7 +216,7 @@ public class Lexer
                         Next();
                     }
 
-                    return new SymbolToken(_sourceFile, startIndex, _index, chain.Value);
+                    return new SymbolToken(_sourceText, startIndex, _index, chain.Value);
                 }
             }
         }
@@ -225,7 +224,7 @@ public class Lexer
         if (Chars.TryGetValue(current, out var charSymbol))
         {
             Next();
-            return new SymbolToken(_sourceFile, startIndex, _index, charSymbol);
+            return new SymbolToken(_sourceText, startIndex, _index, charSymbol);
         }
 
         if (current == '"')
@@ -250,7 +249,7 @@ public class Lexer
                 Next();
             }
 
-            return new LiteralToken(_sourceFile, startIndex, _index, NubPrimitiveType.String, buffer);
+            return new LiteralToken(_sourceText, startIndex, _index, NubPrimitiveType.String, buffer);
         }
 
         throw new Exception($"Unknown character {current}");
@@ -258,9 +257,9 @@ public class Lexer
 
     private Optional<char> Peek(int offset = 0)
     {
-        if (_index + offset < _src.Length)
+        if (_index + offset < _sourceText.Content.Length)
         {
-            return _src[_index + offset];
+            return _sourceText.Content[_index + offset];
         }
 
         return Optional<char>.Empty();
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/LiteralToken.cs b/src/compiler/Nub.Lang/Frontend/Lexing/LiteralToken.cs
index 976a53b..07cad59 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/LiteralToken.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/LiteralToken.cs
@@ -2,7 +2,7 @@
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public class LiteralToken(SourceFile sourceFile, int startIndex, int endIndex, NubType type, string value) : Token(sourceFile, startIndex, endIndex)
+public class LiteralToken(SourceText sourceText, int startIndex, int endIndex, NubType type, string value) : Token(sourceText, startIndex, endIndex)
 {
     public NubType Type { get; } = type;
     public string Value { get; } = value;
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/ModifierToken.cs b/src/compiler/Nub.Lang/Frontend/Lexing/ModifierToken.cs
index d4b2ca6..a6651a0 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/ModifierToken.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/ModifierToken.cs
@@ -2,7 +2,7 @@ using Nub.Lang.Frontend.Diagnostics;
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public class ModifierToken(SourceFile sourceFile, int startIndex, int endIndex, Modifier modifier) : Token(sourceFile, startIndex, endIndex)
+public class ModifierToken(SourceText sourceText, int startIndex, int endIndex, Modifier modifier) : Token(sourceText, startIndex, endIndex)
 {
     public Modifier Modifier { get; } = modifier;
 }
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/SymbolToken.cs b/src/compiler/Nub.Lang/Frontend/Lexing/SymbolToken.cs
index 13223c4..dc063f9 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/SymbolToken.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/SymbolToken.cs
@@ -2,7 +2,7 @@
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public class SymbolToken(SourceFile sourceFile, int startIndex, int endIndex, Symbol symbol) : Token(sourceFile, startIndex, endIndex)
+public class SymbolToken(SourceText sourceText, int startIndex, int endIndex, Symbol symbol) : Token(sourceText, startIndex, endIndex)
 {
     public Symbol Symbol { get; } = symbol;
 }
@@ -10,6 +10,7 @@ public class SymbolToken(SourceFile sourceFile, int startIndex, int endIndex, Sy
 public enum Symbol
 {
     Import,
+    Module,
     Func,
     Return,
     If,
@@ -42,5 +43,5 @@ public enum Symbol
     New,
     Struct,
     Caret,
-    Ampersand
+    Ampersand,
 }
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/Token.cs b/src/compiler/Nub.Lang/Frontend/Lexing/Token.cs
index 1bd7b94..1a46ae8 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/Token.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/Token.cs
@@ -2,9 +2,9 @@
 
 namespace Nub.Lang.Frontend.Lexing;
 
-public abstract class Token(SourceFile sourceFile, int startIndex, int endIndex)
+public abstract class Token(SourceText sourceText, int startIndex, int endIndex)
 {
-    public SourceFile SourceFile { get; } = sourceFile;
+    public SourceText SourceText { get; } = sourceText;
     public int StartIndex { get; } = startIndex;
     public int EndIndex { get; } = endIndex;
 }
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Parsing/ModuleNode.cs b/src/compiler/Nub.Lang/Frontend/Parsing/ModuleNode.cs
deleted file mode 100644
index fd09023..0000000
--- a/src/compiler/Nub.Lang/Frontend/Parsing/ModuleNode.cs
+++ /dev/null
@@ -1,10 +0,0 @@
-using Nub.Lang.Frontend.Lexing;
-
-namespace Nub.Lang.Frontend.Parsing;
-
-public class ModuleNode(IReadOnlyList<Token> tokens, string path, List<string> imports, List<DefinitionNode> definitions) : Node(tokens)
-{
-    public string Path { get; } = path;
-    public List<string> Imports { get; } = imports;
-    public List<DefinitionNode> Definitions { get; } = definitions;
-}
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs b/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
index 2bc9076..f198e35 100644
--- a/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
+++ b/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
@@ -6,41 +6,44 @@ namespace Nub.Lang.Frontend.Parsing;
 
 public class Parser
 {
+    private List<Diagnostic> _diagnostics = [];
     private List<Token> _tokens = [];
     private int _index;
-    private List<Diagnostic> _diagnostics = [];
 
-    public DiagnosticsResult<ModuleNode> ParseModule(List<Token> tokens, string rootFilePath)
+    public DiagnosticsResult<SourceFile?> ParseModule(List<Token> tokens)
     {
-        _index = 0;
-        _tokens = tokens;
         _diagnostics = [];
+        _tokens = tokens;
+        _index = 0;
 
-        List<DefinitionNode> definitions = [];
-        List<string> imports = [];
-
-        while (Peek().HasValue)
+        try
         {
-            try
+            List<string> imports = [];
+            while (TryExpectSymbol(Symbol.Import))
             {
-                if (TryExpectSymbol(Symbol.Import))
-                {
-                    var name = ExpectIdentifier();
-                    imports.Add(name.Value);
-                }
-                else
-                {
-                    definitions.Add(ParseDefinition());
-                }
+                var name = ExpectIdentifier();
+                imports.Add(name.Value);
             }
-            catch (ParseException ex)
+
+            ExpectSymbol(Symbol.Module);
+            var module = ExpectIdentifier().Value;
+
+            List<DefinitionNode> definitions = [];
+
+            while (Peek().HasValue)
             {
-                _diagnostics.Add(ex.Diagnostic);
-                RecoverToNextDefinition();
+                definitions.Add(ParseDefinition());
             }
+            
+            return new DiagnosticsResult<SourceFile?>(_diagnostics, new SourceFile(module, imports, definitions));
+        }
+        catch (ParseException ex)
+        {
+            _diagnostics.Add(ex.Diagnostic);
+            RecoverToNextDefinition();
         }
 
-        return new DiagnosticsResult<ModuleNode>(_diagnostics, new ModuleNode(GetTokensForNode(0), rootFilePath, imports, definitions));
+        return new DiagnosticsResult<SourceFile?>(_diagnostics, null);
     }
 
     private DefinitionNode ParseDefinition()
@@ -567,7 +570,7 @@ public class Parser
             throw new ParseException(Diagnostic
                 .Error("Unexpected end of file while parsing type")
                 .WithHelp("Expected a type name")
-                .At(_tokens.Last().SourceFile, SourceLocationCalculator.GetSpan(_tokens.Last()))
+                .At(_tokens.Last().SourceText, SourceLocationCalculator.GetSpan(_tokens.Last()))
                 .Build());
         }
 
@@ -585,7 +588,7 @@ public class Parser
             throw new ParseException(Diagnostic
                 .Error("Unexpected end of file")
                 .WithHelp("Expected more tokens to complete the syntax")
-                .At(_tokens.Last().SourceFile, SourceLocationCalculator.GetSpan(_tokens.Last()))
+                .At(_tokens.Last().SourceText, SourceLocationCalculator.GetSpan(_tokens.Last()))
                 .Build());
         }
 
diff --git a/src/compiler/Nub.Lang/Frontend/Parsing/SourceFile.cs b/src/compiler/Nub.Lang/Frontend/Parsing/SourceFile.cs
new file mode 100644
index 0000000..0f9642a
--- /dev/null
+++ b/src/compiler/Nub.Lang/Frontend/Parsing/SourceFile.cs
@@ -0,0 +1,8 @@
+namespace Nub.Lang.Frontend.Parsing;
+
+public class SourceFile(string module, List<string> imports, List<DefinitionNode> definitions)
+{
+    public string Module { get; } = module;
+    public List<string> Imports { get; } = imports;
+    public List<DefinitionNode> Definitions { get; } = definitions;
+}
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Frontend/Typing/TypeChecker.cs b/src/compiler/Nub.Lang/Frontend/Typing/TypeChecker.cs
index f2cc226..f06a776 100644
--- a/src/compiler/Nub.Lang/Frontend/Typing/TypeChecker.cs
+++ b/src/compiler/Nub.Lang/Frontend/Typing/TypeChecker.cs
@@ -5,20 +5,20 @@ namespace Nub.Lang.Frontend.Typing;
 
 public class TypeChecker
 {
-    private readonly Dictionary<string, NubType> _variables = new();
-    private readonly List<DefinitionNode> _definitions;
-    private readonly List<Diagnostic> _diagnostics = [];
+    private Dictionary<string, NubType> _variables = new();
+    private List<SourceFile> _sourceFiles = [];
+    private List<Diagnostic> _diagnostics = [];
     private NubType? _currentFunctionReturnType;
     private bool _hasReturnStatement;
+    private List<DefinitionNode> _definitions = [];
 
-    public TypeChecker(List<DefinitionNode> definitions)
+    public DiagnosticsResult<List<DefinitionNode>> TypeCheck(List<SourceFile> sourceFiles)
     {
-        _definitions = definitions;
-    }
-
-    public DiagnosticsResult TypeCheck()
-    {
-        _diagnostics.Clear();
+        _variables = new Dictionary<string, NubType>();
+        _diagnostics = [];
+        _definitions = sourceFiles.SelectMany(x => x.Definitions).ToList();
+        _currentFunctionReturnType = null;
+        _hasReturnStatement = false;
 
         foreach (var structDef in _definitions.OfType<StructDefinitionNode>())
         {
@@ -30,7 +30,7 @@ public class TypeChecker
             TypeCheckFuncDef(funcDef);
         }
 
-        return new DiagnosticsResult(_diagnostics.ToList());
+        return new DiagnosticsResult<List<DefinitionNode>>(_diagnostics, _definitions);
     }
 
     private void TypeCheckStructDef(StructDefinitionNode structDef)
diff --git a/src/compiler/Nub.Lang/Program.cs b/src/compiler/Nub.Lang/Program.cs
index af76aa9..e81dc79 100644
--- a/src/compiler/Nub.Lang/Program.cs
+++ b/src/compiler/Nub.Lang/Program.cs
@@ -1,6 +1,4 @@
-using System.Diagnostics.CodeAnalysis;
-using Nub.Lang.Backend;
-using Nub.Lang.Frontend;
+using Nub.Lang.Backend;
 using Nub.Lang.Frontend.Diagnostics;
 using Nub.Lang.Frontend.Lexing;
 using Nub.Lang.Frontend.Parsing;
@@ -10,94 +8,57 @@ namespace Nub.Lang;
 
 internal static class Program
 {
-    private static readonly Lexer Lexer = new();
-    private static readonly Parser Parser = new();
-
     public static int Main(string[] args)
     {
         if (args.Length != 2)
         {
-            Console.WriteLine("Usage:       nub <input-dir> <output-file>");
-            Console.WriteLine("Example:     nub src out.asm");
+            Console.Error.WriteLine("Usage:       nub <input-dir>");
+            Console.Error.WriteLine("Example:     nub src");
             return 1;
         }
 
-        var input = Path.GetFullPath(args[0]);
-        var output = Path.GetFullPath(args[1]);
+        var srcDir = Path.GetFullPath(args[0]);
 
-        if (!Directory.Exists(input))
+        if (!Directory.Exists(srcDir))
         {
-            Console.WriteLine($"Error: Input directory '{input}' does not exist.");
+            Console.Error.WriteLine($"Error: Input directory '{srcDir}' does not exist.");
             return 1;
         }
 
-        var outputDir = Path.GetDirectoryName(output);
-        if (outputDir == null || !Directory.Exists(outputDir))
-        {
-            Console.WriteLine($"Error: Output directory '{outputDir}' does not exist.");
-            return 1;
-        }
-
-        if (string.IsNullOrWhiteSpace(Path.GetFileName(output)))
-        {
-            Console.WriteLine("Error: Output path must specify a file, not a directory.");
-            return 1;
-        }
-
-        if (TryRunFrontend(input, out var definitions))
-        {
-            return 1;
-        }
-
-        var generator = new Generator(definitions);
-        var result = generator.Generate();
-
-        File.WriteAllText(output, result);
-        return 0;
+        return Compile(srcDir);
     }
 
-    private static bool TryRunFrontend(string rootFilePath, out List<DefinitionNode> definitions)
+    private static int Compile(string srcDir)
     {
-        List<ModuleNode> modules = [];
-        var error = TryRunFrontend(rootFilePath, modules);
-        definitions = modules.SelectMany(f => f.Definitions).ToList();
-        
-        var typeChecker = new TypeChecker(definitions);
-        var typeCheckResult = typeChecker.TypeCheck();
-        typeCheckResult.PrintAllDiagnostics();
-        error = error || typeCheckResult.HasErrors;
-        return error;
-    }
+        var lexer = new Lexer();
+        var parser = new Parser();
+        var typeChecker = new TypeChecker();
 
-    private static bool TryRunFrontend(string rootFilePath, List<ModuleNode> modules)
-    {
-        var error = false;
-        var filePaths = Directory.EnumerateFiles(rootFilePath, "*.nub", SearchOption.TopDirectoryOnly);
-
-        List<Token> tokens = [];
-        foreach (var filePath in filePaths)
+        List<SourceFile> files = [];
+        foreach (var file in Directory.EnumerateFiles(srcDir, "*.nub", SearchOption.AllDirectories))
         {
-            var src = File.ReadAllText(filePath);
-            tokens.AddRange(Lexer.Lex(src, new SourceFile(filePath, src)));
-        }
+            var content = File.ReadAllText(file);
 
-        var parseResult = Parser.ParseModule(tokens, rootFilePath);
-        parseResult.PrintAllDiagnostics();
+            var tokenizeResult = lexer.Tokenize(new SourceText(file, content));
+            tokenizeResult.PrintAllDiagnostics();
 
-        modules.Add(parseResult.Value);
+            var parseResult = parser.ParseModule(tokenizeResult.Value);
+            parseResult.PrintAllDiagnostics();
 
-        foreach (var import in parseResult.Value.Imports)
-        {
-            var importPath = Path.GetFullPath(import, parseResult.Value.Path);
-            if (modules.All(m => m.Path != importPath))
+            if (parseResult.Value != null)
             {
-                if (!TryRunFrontend(importPath, modules))
-                {
-                    error = true;
-                }
+                files.Add(parseResult.Value);
             }
         }
 
-        return error;
+        var typeCheckResult = typeChecker.TypeCheck(files);
+        typeCheckResult.PrintAllDiagnostics();
+
+        var generator = new Generator(typeCheckResult.Value);
+        var result = generator.Generate();
+        
+        Console.Out.Write(result);
+
+        return 0;
     }
 }
\ No newline at end of file