2005-03-16 Alexander Olk <xenomorph2@onlinehome.de>
[mono.git] / mcs / gmcs / namespace.cs
old mode 100755 (executable)
new mode 100644 (file)
index 6e3fbda..ec0a834
@@ -13,8 +13,11 @@ namespace Mono.CSharp {
 
        /// <summary>
        ///   Keeps track of the namespaces defined in the C# code.
+       ///
+       ///   This is an Expression to allow it to be referenced in the
+       ///   compiler parse/intermediate tree during name resolution.
        /// </summary>
-       public class Namespace : IAlias {
+       public class Namespace : FullNamedExpression, IAlias {
                static ArrayList all_namespaces = new ArrayList ();
                static Hashtable namespaces_map = new Hashtable ();
                
@@ -31,6 +34,11 @@ namespace Mono.CSharp {
                /// </summary>
                public Namespace (Namespace parent, string name)
                {
+                       // Expression members.
+                       this.eclass = ExprClass.Namespace;
+                       this.Type = null;
+                       this.loc = Location.Null;
+
                        this.parent = parent;
 
                        string pname = parent != null ? parent.Name : "";
@@ -50,6 +58,16 @@ namespace Mono.CSharp {
                        namespaces_map [fullname] = true;
                }
 
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       return this;
+               }
+
+               public override void Emit (EmitContext ec)
+               {
+                       throw new InternalErrorException ("Expression tree referenced namespace " + fullname + " during Emit ()");
+               }
+
                public static bool IsNamespace (string name)
                {
                        return namespaces_map [name] != null;
@@ -88,17 +106,19 @@ namespace Mono.CSharp {
                        return Root.GetNamespace (name, create);
                }
 
-               public IAlias Lookup (DeclSpace ds, string name, Location loc)
+               public FullNamedExpression Lookup (DeclSpace ds, string name, Location loc)
                {
-                       IAlias o = Lookup (name);
+                       IAlias o = (IAlias) defined_names [name];
 
                        Type t;
                        DeclSpace tdecl = o as DeclSpace;
                        if (tdecl != null) {
                                t = tdecl.DefineType ();
+                               if (t == null)
+                                       return null;
 
                                if ((ds == null) || ds.CheckAccessLevel (t))
-                                       return new TypeExpression (t, loc);
+                                       return new TypeExpression (t, Location.Null);
                        }
 
                        Namespace ns = GetNamespace (name, false);
@@ -109,7 +129,7 @@ namespace Mono.CSharp {
                        if ((t == null) || ((ds != null) && !ds.CheckAccessLevel (t)))
                                return null;
 
-                       return new TypeExpression (t, loc);
+                       return new TypeExpression (t, Location.Null);
                }
 
                public void AddNamespaceEntry (NamespaceEntry entry)
@@ -122,11 +142,6 @@ namespace Mono.CSharp {
                        defined_names.Add (name, o);
                }
 
-               public IAlias Lookup (string name)
-               {
-                       return (IAlias) defined_names [name];
-               }
-
                static public ArrayList UserDefinedNamespaces {
                        get {
                                return all_namespaces;
@@ -142,6 +157,12 @@ namespace Mono.CSharp {
                        }
                }
 
+               public override string FullName {
+                       get {
+                               return fullname;
+                       }
+               }
+
                /// <summary>
                ///   The parent of this namespace, used by the parser to "Pop"
                ///   the current namespace declaration
@@ -184,10 +205,9 @@ namespace Mono.CSharp {
                        get { return false; }
                }
 
-               TypeExpr IAlias.Type {
-                       get {
-                               throw new InvalidOperationException ();
-                       }
+               TypeExpr IAlias.ResolveAsType (EmitContext ec)
+               {
+                       throw new InvalidOperationException ();
                }
        }
 
@@ -227,25 +247,19 @@ namespace Mono.CSharp {
                                if (resolved_ns != null)
                                        return resolved_ns;
 
-                               Namespace curr_ns = NamespaceEntry.NS;
-                               while ((curr_ns != null) && (resolved_ns == null)) {
-                                       resolved_ns = curr_ns.GetNamespace (Name, false);
-
-                                       if (resolved_ns == null)
-                                               curr_ns = curr_ns.Parent;
-                               }
-
+                               FullNamedExpression resolved = NamespaceEntry.LookupForUsing (Name, Location);
+                               resolved_ns = resolved as Namespace;
                                return resolved_ns;
                        }
                }
 
                public class AliasEntry {
                        public readonly string Name;
-                       public readonly TypeName Alias;
+                       public readonly MemberName Alias;
                        public readonly NamespaceEntry NamespaceEntry;
                        public readonly Location Location;
                        
-                       public AliasEntry (NamespaceEntry entry, string name, TypeName alias, Location loc)
+                       public AliasEntry (NamespaceEntry entry, string name, MemberName alias, Location loc)
                        {
                                Name = name;
                                Alias = alias;
@@ -253,36 +267,30 @@ namespace Mono.CSharp {
                                Location = loc;
                        }
 
-                       IAlias resolved;
+                       FullNamedExpression resolved;
 
-                       public IAlias Resolve ()
+                       public FullNamedExpression Resolve ()
                        {
                                if (resolved != null)
                                        return resolved;
 
-                               NamespaceEntry curr_ns = NamespaceEntry;
-
                                //
                                // GENERICS: Cope with the expression and not with the string
                                // this will fail with `using A = Stack<int>'
                                //
                                
-                               string alias = Alias.GetTypeName (true);
-                               while ((curr_ns != null) && (resolved == null)) {
-                                       resolved = curr_ns.Lookup (
-                                               null, alias, Alias.CountTypeArguments,
-                                               Location);
-
-                                       if (resolved == null)
-                                               curr_ns = curr_ns.Parent;
-                               }
+                               string alias = Alias.GetTypeName ();
 
+                               resolved = NamespaceEntry.LookupForUsing (alias, Location);
                                if (resolved == null)
                                        return null;
 
-                               if (resolved.IsType)
-                                       resolved = new TypeAliasExpression (
-                                               resolved.Type, Alias.TypeArguments, Location);
+                               if (Alias.TypeArguments == null)
+                                       return resolved;
+
+                               EmitContext ec = RootContext.Tree.Types.EmitContext;
+                               resolved = new TypeAliasExpression (resolved, Alias.TypeArguments, Location);
+                               resolved = resolved.ResolveAsTypeStep (ec);
 
                                return resolved;
                        }
@@ -359,20 +367,25 @@ namespace Mono.CSharp {
                        if (using_clauses == null)
                                using_clauses = new ArrayList ();
 
-                       foreach (UsingEntry old_entry in using_clauses){
-                               if (old_entry.Name == ns){
-                                       Report.Warning (105, loc, "The using directive for '" + ns +
-                                                       "' appeared previously in this namespace");
-                                       return;
+                       foreach (UsingEntry old_entry in using_clauses) {
+                               if (old_entry.Name == ns) {
+                                       if (RootContext.WarningLevel >= 3)
+                                               Report.Warning (105, loc, "The using directive for '{0}' appeared previously in this namespace", ns);
+                                               return;
+                                       }
                                }
-                       }
                        
                        UsingEntry ue = new UsingEntry (this, ns, loc);
                        using_clauses.Add (ue);
                }
 
-               public void UsingAlias (string name, TypeName alias, Location loc)
+               public void UsingAlias (string name, MemberName alias, Location loc)
                {
+                       if (DeclarationFound){
+                               Report.Error (1529, loc, "A using clause must precede all other namespace elements");
+                               return;
+                       }
+
                        if (aliases == null)
                                aliases = new Hashtable ();
 
@@ -385,43 +398,79 @@ namespace Mono.CSharp {
                        aliases [name] = new AliasEntry (this, name, alias, loc);
                }
 
-               protected AliasEntry GetAliasEntry (string alias)
+               public FullNamedExpression LookupAlias (string alias)
                {
                        AliasEntry entry = null;
-
                        if (aliases != null)
                                entry = (AliasEntry) aliases [alias];
-                       if (entry == null && Parent != null)
-                               entry = Parent.GetAliasEntry (alias);
 
-                       return entry;
+                       return entry == null ? null : entry.Resolve ();
                }
 
-               public IAlias LookupAlias (string alias)
+               //
+               // According to section 16.3.1 (using-alias-directive), the namespace-or-type-name is 
+               // resolved as if the immediately containing namespace body has no using-directives.
+               //
+               // Section 16.3.2 says that the same rule is applied when resolving the namespace-name
+               // in the using-namespace-directive.
+               //
+               public FullNamedExpression LookupForUsing (string dotted_name, Location loc)
                {
-                       AliasEntry entry = GetAliasEntry (alias);
+                       int pos = dotted_name.IndexOf ('.');
+                       string simple_name = dotted_name;
+                       string rest = null;
+                       if (pos >= 0) {
+                               simple_name = dotted_name.Substring (0, pos);
+                               rest = dotted_name.Substring (pos + 1);
+                       }
+
+                       FullNamedExpression o = NS.Lookup (null, simple_name, loc);
+                       if (o == null && ImplicitParent != null)
+                               o = ImplicitParent.LookupNamespaceOrType (null, simple_name, loc);
+
+                       if (o == null || rest == null)
+                               return o;
 
-                       if (entry == null)
+                       Namespace ns = o as Namespace;
+                       if (ns != null)
+                               return ns.Lookup (null, rest, loc);
+                       
+                       Type nested = TypeManager.LookupType (o.FullName + "." + rest);
+                       if (nested == null)
                                return null;
 
-                       return entry.Resolve ();
+                       return new TypeExpression (nested, Location.Null);
                }
 
-               public IAlias Lookup (DeclSpace ds, string name, int num_type_params,
-                                     Location loc)
+               public FullNamedExpression LookupNamespaceOrType (DeclSpace ds, string name, Location loc)
                {
-                       IAlias o;
+                       FullNamedExpression resolved = null;
+                       for (NamespaceEntry curr_ns = this; curr_ns != null; curr_ns = curr_ns.ImplicitParent) {
+                               if ((resolved = curr_ns.Lookup (ds, name, loc)) != null)
+                                       break;
+                       }
+                       return resolved;
+               }
+
+               private FullNamedExpression Lookup (DeclSpace ds, string name, Location loc)
+               {
+                       FullNamedExpression o;
                        Namespace ns;
 
                        //
                        // If name is of the form `N.I', first lookup `N', then search a member `I' in it.
                        //
+                       // FIXME: Remove this block.  Only simple names should come here.
+                       //        The bug: The loop in LookupNamespaceOrType continues if 
+                       //        the lookup for N succeeds but the nested lookup for I fails.
+                       //        This is one part of #52697.
+                       //
                        int pos = name.IndexOf ('.');
                        if (pos >= 0) {
                                string first = name.Substring (0, pos);
                                string last = name.Substring (pos + 1);
 
-                               o = Lookup (ds, first, 0, loc);
+                               o = Lookup (ds, first, loc);
                                if (o == null)
                                        return null;
 
@@ -431,15 +480,15 @@ namespace Mono.CSharp {
                                        return o;
                                }
 
-                               Type nested = TypeManager.LookupType (o.Name + "." + last);
+                               Type nested = TypeManager.LookupType (o.FullName + "." + last);
                                if ((nested == null) || ((ds != null) && !ds.CheckAccessLevel (nested)))
                                        return null;
 
-                               return new TypeExpression (nested, loc);
+                               return new TypeExpression (nested, Location.Null);
                        }
 
                        //
-                       // Check whether it's a namespace.
+                       // Check whether it's in the namespace.
                        //
                        o = NS.Lookup (ds, name, loc);
                        if (o != null)
@@ -448,22 +497,22 @@ namespace Mono.CSharp {
                        //
                        // Check aliases.
                        //
-                       AliasEntry entry = GetAliasEntry (name);
-                       if (entry != null) {
-                               IAlias alias = entry.Resolve ();
-                               if (alias != null)
-                                       return alias;
-                       }
+                       o = LookupAlias (name);
+                       if (o != null)
+                               return o;
+
+                       if (name.IndexOf ('.') > 0)
+                               return null;
 
                        //
                        // Check using entries.
                        //
-                       IAlias t = null, match = null;
+                       FullNamedExpression t = null, match = null;
                        foreach (Namespace using_ns in GetUsingTable ()) {
                                match = using_ns.Lookup (ds, name, loc);
-                               if ((match != null) && match.IsType){
+                               if ((match != null) && (match is TypeExpr)) {
                                        if (t != null) {
-                                               DeclSpace.Error_AmbiguousTypeReference (loc, name, t.Name, match.Name);
+                                               DeclSpace.Error_AmbiguousTypeReference (loc, name, t.FullName, match.FullName);
                                                return null;
                                        } else {
                                                t = match;
@@ -480,9 +529,11 @@ namespace Mono.CSharp {
                {
                        if (namespace_using_table != null)
                                return namespace_using_table;
-                       
-                       if (using_clauses == null)
-                               return new Namespace [0];
+
+                       if (using_clauses == null) {
+                               namespace_using_table = new Namespace [0];
+                               return namespace_using_table;
+                       }
 
                        ArrayList list = new ArrayList (using_clauses.Count);
 
@@ -516,7 +567,11 @@ namespace Mono.CSharp {
                        }
 
                        int parent_id = parent != null ? parent.symfile_id : 0;
-                       symfile_id = symwriter.DefineNamespace (ns.Name, file, using_list, parent_id);
+                       if (file.SourceFileEntry == null)
+                               return;
+
+                       symfile_id = symwriter.DefineNamespace (
+                               ns.Name, file.SourceFileEntry, using_list, parent_id);
                }
 
                public int SymbolFileID {
@@ -525,53 +580,41 @@ namespace Mono.CSharp {
                        }
                }
 
-               static void Msgtry (string s)
+               static void MsgtryRef (string s)
                {
                        Console.WriteLine ("    Try using -r:" + s);
                }
+               
+               static void MsgtryPkg (string s)
+               {
+                       Console.WriteLine ("    Try using -pkg:" + s);
+               }
 
                protected void error246 (Location loc, string name)
                {
-                       if (TypeManager.LookupType (name) != null)
-                               Report.Error (138, loc, "The using keyword only lets you specify a namespace, " +
-                                             "`" + name + "' is a class not a namespace.");
-                       else {
-                               Report.Error (246, loc, "The namespace `" + name +
-                                             "' can not be found (missing assembly reference?)");
-
-                               switch (name){
-                               case "Gtk": case "GtkSharp":
-                                       Msgtry ("gtk-sharp");
-                                       break;
-
-                               case "Gdk": case "GdkSharp":
-                                       Msgtry ("gdk-sharp");
-                                       break;
-
-                               case "Glade": case "GladeSharp":
-                                       Msgtry ("glade-sharp");
-                                       break;
-                                                       
-                               case "System.Drawing":
-                                       Msgtry ("System.Drawing");
-                                       break;
-                                                       
-                               case "System.Web.Services":
-                                       Msgtry ("System.Web.Services");
-                                       break;
-
-                               case "System.Web":
-                                       Msgtry ("System.Web");
-                                       break;
-                                                       
-                               case "System.Data":
-                                       Msgtry ("System.Data");
-                                       break;
-
-                               case "System.Windows.Forms":
-                                       Msgtry ("System.Windows.Forms");
-                                       break;
-                               }
+                       Report.Error (246, loc, "The namespace `" + name +
+                                     "' can not be found (missing assembly reference?)");
+
+                       switch (name) {
+                       case "Gtk": case "GtkSharp":
+                               MsgtryPkg ("gtk-sharp");
+                               break;
+
+                       case "Gdk": case "GdkSharp":
+                               MsgtryPkg ("gdk-sharp");
+                               break;
+
+                       case "Glade": case "GladeSharp":
+                               MsgtryPkg ("glade-sharp");
+                               break;
+
+                       case "System.Drawing":
+                       case "System.Web.Services":
+                       case "System.Web":
+                       case "System.Data":
+                       case "System.Windows.Forms":
+                               MsgtryRef (name);
+                               break;
                        }
                }
 
@@ -581,32 +624,28 @@ namespace Mono.CSharp {
                /// </summary>
                public void VerifyUsing ()
                {
-                       TypeContainer dummy = new TypeContainer ();
-                       EmitContext ec = new EmitContext (
-                               dummy, Location.Null, null, null, 0, false);
-
                        if (using_clauses != null){
                                foreach (UsingEntry ue in using_clauses){
                                        if (ue.Resolve () != null)
                                                continue;
 
-                                       error246 (ue.Location, ue.Name);
+                                       if (LookupForUsing (ue.Name, ue.Location) == null)
+                                               error246 (ue.Location, ue.Name);
+                                       else
+                                               Report.Error (138, ue.Location, "The using keyword only lets you specify a namespace, " +
+                                                             "`" + ue.Name + "' is a class not a namespace.");
+
                                }
                        }
 
                        if (aliases != null){
                                foreach (DictionaryEntry de in aliases){
-                                       AliasEntry entry = (AliasEntry) de.Value;
-
-                                       IAlias alias = entry.Resolve ();
-                                       if (alias != null) {
-                                               if (alias.IsType)
-                                                       alias.Type.ResolveType (ec);
+                                       AliasEntry alias = (AliasEntry) de.Value;
 
+                                       if (alias.Resolve () != null)
                                                continue;
-                                       }
 
-                                       error246 (entry.Location, entry.Alias.ToString ());
+                                       error246 (alias.Location, alias.Alias.GetTypeName ());
                                }
                        }
                }