src/Boo.Lang/Runtime/ExtensionRegistry.cs

   1 #region license
   2 // Copyright (c) 2003, 2004, 2005 Rodrigo B. de Oliveira (rbo@acm.org)
   3 // All rights reserved.
   4 //
   5 // Redistribution and use in source and binary forms, with or without modification,
   6 // are permitted provided that the following conditions are met:
   7 //
   8 //     * Redistributions of source code must retain the above copyright notice,
   9 //     this list of conditions and the following disclaimer.
  10 //     * Redistributions in binary form must reproduce the above copyright notice,
  11 //     this list of conditions and the following disclaimer in the documentation
  12 //     and/or other materials provided with the distribution.
  13 //     * Neither the name of Rodrigo B. de Oliveira nor the names of its
  14 //     contributors may be used to endorse or promote products derived from this
  15 //     software without specific prior written permission.
  16 //
  17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
  18 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
  21 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  25 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26 // THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27 #endregion
  28
  29
  30 using System;
  31 using System.Collections.Generic;
  32 using System.Reflection;
  33
  34 namespace Boo.Lang.Runtime
  35 {
  36         public class ExtensionRegistry
  37         {
  38                 private List<MemberInfo> _extensions = new List<MemberInfo>();
  39
  40                 public void Register(Type type)
  41                 {
  42                         lock (this)
  43                         {
  44                                 _extensions = AddExtensionMembers(CopyExtensions(), type);
  45                         }
  46                 }
  47
  48                 public IEnumerable<MemberInfo> Extensions
  49                 {
  50                         get { lock(this) { return _extensions; }  }
  51                 }
  52
  53                 public void UnRegister(Type type)
  54                 {
  55                         lock (this)
  56                         {
  57                                 List<MemberInfo> extensions = CopyExtensions();
  58                                 extensions.RemoveAll(delegate(MemberInfo member) { return member.DeclaringType == type; });
  59                                 _extensions = extensions;
  60                         }
  61                 }
  62
  63                 private static List<MemberInfo> AddExtensionMembers(List<MemberInfo> extensions, Type type)
  64                 {
  65                         foreach (MemberInfo member in type.GetMembers(BindingFlags.Static | BindingFlags.Public))
  66                         {
  67                                 if (!Attribute.IsDefined(member, typeof(Boo.Lang.ExtensionAttribute))) continue;
  68                                 if (extensions.Contains(member)) continue;
  69                                 extensions.Add(member);
  70                         }
  71                         return extensions;
  72                 }
  73
  74                 private List<MemberInfo> CopyExtensions()
  75                 {
  76                         return new List<MemberInfo>(_extensions);
  77                 }
  78         }
  79 }