//
// namespace.cs: Tracks namespaces
//
// Author:
// Miguel de Icaza (miguel@ximian.com)
//
// (C) 2001 Ximian, Inc.
//
using System;
using System.Collections;
namespace Mono.CSharp {
///
/// Keeps track of the namespaces defined in the C# code.
///
public class Namespace : IAlias {
static ArrayList all_namespaces = new ArrayList ();
static Hashtable namespaces_map = new Hashtable ();
Namespace parent;
string fullname;
ArrayList entries;
Hashtable namespaces;
Hashtable defined_names;
///
/// Constructor Takes the current namespace and the
/// name. This is bootstrapped with parent == null
/// and name = ""
///
public Namespace (Namespace parent, string name)
{
this.parent = parent;
string pname = parent != null ? parent.Name : "";
if (pname == "")
fullname = name;
else
fullname = parent.Name + "." + name;
entries = new ArrayList ();
namespaces = new Hashtable ();
defined_names = new Hashtable ();
all_namespaces.Add (this);
if (namespaces_map.Contains (fullname))
return;
namespaces_map [fullname] = true;
}
public static bool IsNamespace (string name)
{
return namespaces_map [name] != null;
}
public static Namespace Root = new Namespace (null, "");
public Namespace GetNamespace (string name, bool create)
{
int pos = name.IndexOf ('.');
Namespace ns;
string first;
if (pos >= 0)
first = name.Substring (0, pos);
else
first = name;
ns = (Namespace) namespaces [first];
if (ns == null) {
if (!create)
return null;
ns = new Namespace (this, first);
namespaces.Add (first, ns);
}
if (pos >= 0)
ns = ns.GetNamespace (name.Substring (pos + 1), create);
return ns;
}
public static Namespace LookupNamespace (string name, bool create)
{
return Root.GetNamespace (name, create);
}
public IAlias Lookup (DeclSpace ds, string name, Location loc)
{
IAlias o = Lookup (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);
}
Namespace ns = GetNamespace (name, false);
if (ns != null)
return ns;
t = TypeManager.LookupType (DeclSpace.MakeFQN (fullname, name));
if ((t == null) || ((ds != null) && !ds.CheckAccessLevel (t)))
return null;
return new TypeExpression (t, loc);
}
public void AddNamespaceEntry (NamespaceEntry entry)
{
entries.Add (entry);
}
public void DefineName (string name, IAlias o)
{
defined_names.Add (name, o);
}
public IAlias Lookup (string name)
{
return (IAlias) defined_names [name];
}
static public ArrayList UserDefinedNamespaces {
get {
return all_namespaces;
}
}
///
/// The qualified name of the current namespace
///
public string Name {
get {
return fullname;
}
}
///
/// The parent of this namespace, used by the parser to "Pop"
/// the current namespace declaration
///
public Namespace Parent {
get {
return parent;
}
}
public static void DefineNamespaces (SymbolWriter symwriter)
{
foreach (Namespace ns in all_namespaces) {
foreach (NamespaceEntry entry in ns.entries)
entry.DefineNamespace (symwriter);
}
}
///
/// Used to validate that all the using clauses are correct
/// after we are finished parsing all the files.
///
public static void VerifyUsing ()
{
foreach (Namespace ns in all_namespaces) {
foreach (NamespaceEntry entry in ns.entries)
entry.VerifyUsing ();
}
}
public override string ToString ()
{
if (this == Root)
return "Namespace ()";
else
return String.Format ("Namespace ({0})", Name);
}
bool IAlias.IsType {
get { return false; }
}
TypeExpr IAlias.ResolveAsType (EmitContext ec)
{
throw new InvalidOperationException ();
}
}
public class NamespaceEntry
{
Namespace ns;
NamespaceEntry parent, implicit_parent;
SourceFile file;
int symfile_id;
Hashtable aliases;
ArrayList using_clauses;
public bool DeclarationFound = false;
//
// This class holds the location where a using definition is
// done, and whether it has been used by the program or not.
//
// We use this to flag using clauses for namespaces that do not
// exist.
//
public class UsingEntry {
public readonly string Name;
public readonly NamespaceEntry NamespaceEntry;
public readonly Location Location;
public UsingEntry (NamespaceEntry entry, string name, Location loc)
{
Name = name;
NamespaceEntry = entry;
Location = loc;
}
Namespace resolved_ns;
public Namespace Resolve ()
{
if (resolved_ns != null)
return resolved_ns;
object resolved = NamespaceEntry.LookupForUsing (Name, Location);
resolved_ns = resolved as Namespace;
return resolved_ns;
}
}
public class AliasEntry {
public readonly string Name;
public readonly MemberName Alias;
public readonly NamespaceEntry NamespaceEntry;
public readonly Location Location;
public AliasEntry (NamespaceEntry entry, string name, MemberName alias, Location loc)
{
Name = name;
Alias = alias;
NamespaceEntry = entry;
Location = loc;
}
IAlias resolved;
public IAlias Resolve ()
{
if (resolved != null)
return resolved;
//
// GENERICS: Cope with the expression and not with the string
// this will fail with `using A = Stack'
//
string alias = Alias.GetTypeName ();
resolved = NamespaceEntry.LookupForUsing (alias, Location);
if (resolved == null)
return null;
if (resolved.IsType)
resolved = new TypeAliasExpression (
resolved, Alias.TypeArguments, Location);
return resolved;
}
}
public NamespaceEntry (NamespaceEntry parent, SourceFile file, string name, Location loc)
: this (parent, file, name, false, loc)
{ }
protected NamespaceEntry (NamespaceEntry parent, SourceFile file, string name, bool is_implicit, Location loc)
{
this.parent = parent;
this.file = file;
this.IsImplicit = is_implicit;
this.ID = ++next_id;
if (!is_implicit && (parent != null))
ns = parent.NS.GetNamespace (name, true);
else if (name != null)
ns = Namespace.LookupNamespace (name, true);
else
ns = Namespace.Root;
ns.AddNamespaceEntry (this);
if ((parent != null) && (parent.NS != ns.Parent))
implicit_parent = new NamespaceEntry (parent, file, ns.Parent.Name, true, loc);
else
implicit_parent = parent;
this.FullName = ns.Name;
}
static int next_id = 0;
public readonly string FullName;
public readonly int ID;
public readonly bool IsImplicit;
public Namespace NS {
get {
return ns;
}
}
public NamespaceEntry Parent {
get {
return parent;
}
}
public NamespaceEntry ImplicitParent {
get {
return implicit_parent;
}
}
public void DefineName (string name, IAlias o)
{
ns.DefineName (name, o);
}
///
/// Records a new namespace for resolving name references
///
public void Using (string ns, Location loc)
{
if (DeclarationFound){
Report.Error (1529, loc, "A using clause must precede all other namespace elements");
return;
}
if (ns == FullName)
return;
if (using_clauses == null)
using_clauses = new ArrayList ();
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, 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 ();
if (aliases.Contains (name)){
Report.Error (1537, loc, "The using alias `" + name +
"' appeared previously in this namespace");
return;
}
aliases [name] = new AliasEntry (this, name, alias, loc);
}
protected AliasEntry GetAliasEntry (string alias)
{
AliasEntry entry = null;
if (aliases != null)
entry = (AliasEntry) aliases [alias];
if (entry == null && Parent != null)
entry = Parent.GetAliasEntry (alias);
return entry;
}
public IAlias LookupAlias (string alias)
{
AliasEntry entry = GetAliasEntry (alias);
if (entry == null)
return null;
return entry.Resolve ();
}
//
// 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 IAlias LookupForUsing (string dotted_name, Location loc)
{
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);
}
IAlias 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;
Namespace ns = o as Namespace;
if (ns != null)
return ns.Lookup (null, rest, loc);
Type nested = TypeManager.LookupType (o.Name + "." + rest);
if (nested == null)
return null;
return new TypeExpression (nested, loc);
}
public IAlias LookupNamespaceOrType (DeclSpace ds, string name, Location loc)
{
IAlias 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 IAlias Lookup (DeclSpace ds, string name, Location loc)
{
IAlias 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, loc);
if (o == null)
return null;
ns = o as Namespace;
if (ns != null) {
o = ns.Lookup (ds, last, loc);
return o;
}
Type nested = TypeManager.LookupType (o.Name + "." + last);
if ((nested == null) || ((ds != null) && !ds.CheckAccessLevel (nested)))
return null;
return new TypeExpression (nested, loc);
}
//
// Check whether it's in the namespace.
//
o = NS.Lookup (ds, name, loc);
if (o != null)
return o;
//
// Check aliases.
//
AliasEntry entry = GetAliasEntry (name);
if (entry != null) {
IAlias alias = entry.Resolve ();
if (alias != null)
return alias;
}
if (name.IndexOf ('.') > 0)
return null;
//
// Check using entries.
//
IAlias t = null, match = null;
foreach (Namespace using_ns in GetUsingTable ()) {
match = using_ns.Lookup (ds, name, loc);
if ((match != null) && match.IsType){
if (t != null) {
DeclSpace.Error_AmbiguousTypeReference (loc, name, t.Name, match.Name);
return null;
} else {
t = match;
}
}
}
return t;
}
// Our cached computation.
Namespace [] namespace_using_table;
public Namespace[] GetUsingTable ()
{
if (namespace_using_table != null)
return namespace_using_table;
if (using_clauses == null)
return new Namespace [0];
ArrayList list = new ArrayList (using_clauses.Count);
foreach (UsingEntry ue in using_clauses) {
Namespace using_ns = ue.Resolve ();
if (using_ns == null)
continue;
list.Add (using_ns);
}
namespace_using_table = new Namespace [list.Count];
list.CopyTo (namespace_using_table, 0);
return namespace_using_table;
}
public void DefineNamespace (SymbolWriter symwriter)
{
if (symfile_id != 0)
return;
if (parent != null)
parent.DefineNamespace (symwriter);
string[] using_list;
if (using_clauses != null) {
using_list = new string [using_clauses.Count];
for (int i = 0; i < using_clauses.Count; i++)
using_list [i] = ((UsingEntry) using_clauses [i]).Name;
} else {
using_list = new string [0];
}
int parent_id = parent != null ? parent.symfile_id : 0;
if (file.SourceFileEntry == null)
return;
symfile_id = symwriter.DefineNamespace (
ns.Name, file.SourceFileEntry, using_list, parent_id);
}
public int SymbolFileID {
get {
return symfile_id;
}
}
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)
{
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;
}
}
///
/// Used to validate that all the using clauses are correct
/// after we are finished parsing all the files.
///
public void VerifyUsing ()
{
TypeContainer dummy = new RootTypes ();
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;
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.ResolveAsType (ec);
continue;
}
error246 (entry.Location, entry.Alias.GetTypeName ());
}
}
}
public override string ToString ()
{
if (NS == Namespace.Root)
return "NamespaceEntry ()";
else
return String.Format ("NamespaceEntry ({0},{1},{2})", FullName, IsImplicit, ID);
}
}
}