mcs/mbas/namespace.cs

   1 //
   2 // namespace.cs: Tracks namespaces
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //
   7 // (C) 2001 Ximian, Inc.
   8 //
   9 using System;
  10 using System.Collections;
  11 using Mono.Languages;
  12
  13 namespace Mono.CSharp {
  14
  15         /// <summary>
  16         ///   Keeps track of the namespaces defined in the C# code.
  17         /// </summary>
  18         public class Namespace {
  19                 Namespace parent;
  20                 string name;
  21                 ArrayList using_clauses;
  22                 Hashtable aliases;
  23                 public bool DeclarationFound = false;
  24
  25                 /// <summary>
  26                 ///   Constructor Takes the current namespace and the
  27                 ///   name.  This is bootstrapped with parent == null
  28                 ///   and name = ""
  29                 /// </summary>
  30                 public Namespace (Namespace parent, string name)
  31                 {
  32                         this.name = name;
  33                         this.parent = parent;
  34                 }
  35
  36                 /// <summary>
  37                 ///   The qualified name of the current namespace
  38                 /// </summary>
  39                 public string Name {
  40                         get {
  41                                 string pname = parent != null ? parent.Name : "";
  42
  43                                 if (pname == "")
  44                                         return name;
  45                                 else
  46                                         return parent.Name + "." + name;
  47                         }
  48                 }
  49
  50                 /// <summary>
  51                 ///   The parent of this namespace, used by the parser to "Pop"
  52                 ///   the current namespace declaration
  53                 /// </summary>
  54                 public Namespace Parent {
  55                         get {
  56                                 return parent;
  57                         }
  58                 }
  59
  60                 /// <summary>
  61                 ///   Records a new namespace for resolving name references
  62                 /// </summary>
  63                 public void Using (string ns, Location loc)
  64                 {
  65                         if (DeclarationFound){
  66                                 Report.Error (1529, loc, "A using clause must precede all other namespace elements");
  67                                 return;
  68                         }
  69
  70                         if (using_clauses == null)
  71                                 using_clauses = new ArrayList ();
  72
  73                         using_clauses.Add (ns);
  74                 }
  75
  76                 public ArrayList UsingTable {
  77                         get {
  78                                 return using_clauses;
  79                         }
  80                 }
  81
  82                 public void UsingAlias (string alias, string namespace_or_type, Location loc)
  83                 {
  84                         if (aliases == null)
  85                                 aliases = new Hashtable ();
  86
  87                         if (aliases.Contains (alias)){
  88                                 Report.Error (1537, loc, "The using alias `" + alias +
  89                                               "' appeared previously in this namespace");
  90                                 return;
  91                         }
  92
  93                         aliases [alias] = namespace_or_type;
  94                 }
  95
  96                 public string LookupAlias (string alias)
  97                 {
  98                         string value = null;
  99
 100                         // System.Console.WriteLine ("Lookup " + alias + " in " + name);
 101
 102                         if (aliases != null)
 103                                 value = (string) (aliases [alias]);
 104                         if (value == null && Parent != null)
 105                                 value = Parent.LookupAlias (alias);
 106
 107                         return value;
 108                 }
 109
 110                 /// <summary>
 111                 ///   Used to validate that all the using clauses are correct
 112                 ///   after we are finished parsing all the files
 113                 /// </summary>
 114                 public void VerifyUsing ()
 115                 {
 116                         foreach (DictionaryEntry de in using_clauses){
 117                                 if (de.Value == null){
 118                                         string name = (string) de.Key;
 119
 120                                         Report.Error (234, "The type or namespace `" +
 121                                                             name + "' does not exist in the " +
 122                                                             "class or namespace `" + name + "'");
 123                                 }
 124                         }
 125                 }
 126
 127         }
 128 }
 129