mcs/tools/mdoc/Mono.Rocks/ObjectRocks.cs

   1 //
   2 // Object.cs: C# extension methods on object.
   3 //
   4 // Author:
   5 //   Jonathan Pryor  <jpryor@novell.com>
   6 //   leppie  (http://xacc.wordpress.com/)
   7 //
   8 // Copyright (c) 2008-2009 Novell, Inc. (http://www.novell.com)
   9 // Copyright (c) 2009 leppie (http://xacc.wordpress.com/)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30 using System;
  31 using System.Collections.Generic;
  32 using System.Linq;
  33 using System.Linq.Expressions;
  34
  35 namespace Mono.Rocks {
  36
  37         static class Check {
  38                 public static void ChildrenSelector (object childrenSelector)
  39                 {
  40                         if (childrenSelector == null)
  41                                 throw new ArgumentNullException ("childrenSelector");
  42                 }
  43
  44                 public static void Destination (object destination)
  45                 {
  46                         if (destination == null)
  47                                 throw new ArgumentNullException ("destination");
  48                 }
  49
  50                 public static void Self (object self)
  51                 {
  52                         if (self == null)
  53                                 throw new ArgumentNullException ("self");
  54                 }
  55
  56                 public static void ValueSelector (object valueSelector)
  57                 {
  58                         if (valueSelector == null)
  59                                 throw new ArgumentNullException ("valueSelector");
  60                 }
  61         }
  62
  63         public static class ObjectRocks {
  64
  65                 #region Tree Traversal Methods
  66
  67                 /*
  68                  * Tree Traversal Methods courtesy of:
  69                  * http://xacc.wordpress.com/2009/03/05/tree-traversal-extension-methods/
  70                  */
  71
  72                 public static IEnumerable<TResult> TraverseDepthFirst<TSource, TResult>(
  73                                 this TSource self,
  74                                 Func<TSource, TResult> valueSelector,
  75                                 Func<TSource, IEnumerable<TSource>> childrenSelector)
  76                 {
  77                         return self.TraverseDepthFirstWithParent (valueSelector, childrenSelector)
  78                                 .Select(x => x.Value);
  79                 }
  80
  81                 public static IEnumerable<KeyValuePair<TSource, TResult>> TraverseDepthFirstWithParent<TSource, TResult>(
  82                                 this TSource self,
  83                                 Func<TSource, TResult> valueSelector,
  84                                 Func<TSource, IEnumerable<TSource>> childrenSelector)
  85                 {
  86                         return self.TraverseDepthFirstWithParent (default (TSource), valueSelector, childrenSelector);
  87                 }
  88
  89                 static IEnumerable<KeyValuePair<TSource, TResult>> TraverseDepthFirstWithParent<TSource, TResult>(
  90                                 this TSource self,
  91                                 TSource parent,
  92                                 Func<TSource, TResult> valueSelector,
  93                                 Func<TSource, IEnumerable<TSource>> childrenSelector)
  94                 {
  95                         Check.Self (self);
  96                         Check.ValueSelector (valueSelector);
  97                         Check.ChildrenSelector (childrenSelector);
  98
  99                         return CreateTraverseDepthFirstWithParentIterator (self, parent, valueSelector, childrenSelector);
 100                 }
 101
 102                 static IEnumerable<KeyValuePair<TSource, TResult>> CreateTraverseDepthFirstWithParentIterator<TSource, TResult>(
 103                                 this TSource self,
 104                                 TSource parent,
 105                                 Func<TSource, TResult> valueSelector,
 106                                 Func<TSource, IEnumerable<TSource>> childrenSelector)
 107                 {
 108                         yield return new KeyValuePair<TSource, TResult>(parent, valueSelector (self));
 109
 110                         foreach (var c in childrenSelector (self))
 111                         {
 112                                 foreach (var item in c.TraverseDepthFirstWithParent(c, valueSelector, childrenSelector))
 113                                 {
 114                                         yield return item;
 115                                 }
 116                         }
 117                 }
 118                 #endregion
 119         }
 120 }
 121