module exports and name mangling

compiler/Parser.cs

@@ -43,8 +43,38 @@ public sealed class Parser(string fileName, List<Token> tokens)
     {
         var startIndex = index;
 
+        Dictionary<Keyword, TokenKeyword> modifiers = [];
+
+        while (true)
+        {
+            if (Peek() is TokenKeyword keyword)
+            {
+                switch (keyword.Keyword)
+                {
+                    case Keyword.Export:
+                        Next();
+                        modifiers[Keyword.Export] = keyword;
+                        break;
+                    case Keyword.Packed:
+                        Next();
+                        modifiers[Keyword.Packed] = keyword;
+                        break;
+                    default:
+                        goto modifier_done;
+                }
+            }
+        }
+
+        modifier_done:
+
         if (TryExpectKeyword(Keyword.Func))
         {
+            var exported = modifiers.Remove(Keyword.Export);
+
+            foreach (var modifier in modifiers)
+                // todo(nub31): Add to diagnostics instead of throwing
+                throw new CompileException(Diagnostic.Error("Invalid modifier for function").At(fileName, modifier.Value).Build());
+
             var name = ExpectIdent();
             var parameters = new List<NodeDefinitionFunc.Param>();
 
@@ -63,11 +93,18 @@ public sealed class Parser(string fileName, List<Token> tokens)
 
             var body = ParseStatement();
 
-            return new NodeDefinitionFunc(TokensFrom(startIndex), name, parameters, body, returnType);
+            return new NodeDefinitionFunc(TokensFrom(startIndex), exported, name, parameters, body, returnType);
         }
 
         if (TryExpectKeyword(Keyword.Struct))
         {
+            var exported = modifiers.Remove(Keyword.Export);
+            var packed = modifiers.Remove(Keyword.Packed);
+
+            foreach (var modifier in modifiers)
+                // todo(nub31): Add to diagnostics instead of throwing
+                throw new CompileException(Diagnostic.Error("Invalid modifier for struct").At(fileName, modifier.Value).Build());
+
             var name = ExpectIdent();
             var fields = new List<NodeDefinitionStruct.Field>();
 
@@ -81,7 +118,7 @@ public sealed class Parser(string fileName, List<Token> tokens)
                 fields.Add(new NodeDefinitionStruct.Field(TokensFrom(fieldStartIndex), fieldName, fieldType));
             }
 
-            return new NodeDefinitionStruct(TokensFrom(startIndex), name, fields);
+            return new NodeDefinitionStruct(TokensFrom(startIndex), exported, packed, name, fields);
         }
 
         throw new CompileException(Diagnostic.Error("Not a valid definition").At(fileName, Peek()).Build());
@@ -556,8 +593,9 @@ public abstract class Node(List<Token> tokens)
 
 public abstract class NodeDefinition(List<Token> tokens) : Node(tokens);
 
-public sealed class NodeDefinitionFunc(List<Token> tokens, TokenIdent name, List<NodeDefinitionFunc.Param> parameters, NodeStatement body, NodeType returnType) : NodeDefinition(tokens)
+public sealed class NodeDefinitionFunc(List<Token> tokens, bool exported, TokenIdent name, List<NodeDefinitionFunc.Param> parameters, NodeStatement body, NodeType returnType) : NodeDefinition(tokens)
 {
+    public bool Exported { get; } = exported;
     public TokenIdent Name { get; } = name;
     public List<Param> Parameters { get; } = parameters;
     public NodeStatement Body { get; } = body;
@@ -570,8 +608,10 @@ public sealed class NodeDefinitionFunc(List<Token> tokens, TokenIdent name, List
     }
 }
 
-public sealed class NodeDefinitionStruct(List<Token> tokens, TokenIdent name, List<NodeDefinitionStruct.Field> fields) : NodeDefinition(tokens)
+public sealed class NodeDefinitionStruct(List<Token> tokens, bool exported, bool packed, TokenIdent name, List<NodeDefinitionStruct.Field> fields) : NodeDefinition(tokens)
 {
+    public bool Exported { get; } = exported;
+    public bool Packed { get; } = packed;
     public TokenIdent Name { get; } = name;
     public List<Field> Fields { get; } = fields;