xronos /System.Xronos/Language/PersistentList.cs

Language C# Lines 259
MD5 Hash 3f9d6c7e0f74e89b6ac5ad2c3226f38a Estimated Cost $4,516 (why?)
Repository https://bitbucket.org/stefanrusek/xronos View Raw File
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
/* ****************************************************************************
 * 
 * Copyright (c) 2008 Stefan Rusek and Benjamin Pollack
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 * 
 * ***************************************************************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;

namespace System.Xronos.Language
{
    public class PersistentList : Sequence, IPersistentList, IReduce
    {
        object _first;
        PersistentList _rest;
        int _count;

        private PersistentList(IPersistentMap meta, object first, PersistentList rest)
            : base(meta)
        {
            _first = first;
            _rest = rest;

            if (rest != null)
                _count = rest.Count;

            _count++;
        }

        public static IPersistentList Create(IList list)
        {
            IPersistentCollection rt = Empty;
            for (int i = list.Count-1; i >= 0; i--)
            {
                rt = rt.cons(list[i]);
            }
            return (IPersistentList)rt;
        }

        public static IPersistentList Create(ISequence seq)
        {
            if (seq == null)
                return Empty;
            return (IPersistentList)Create(seq.rest()).cons(seq.first());
        }

        public static readonly IPersistentList Empty = new EmptyList();

        public override object first()
        {
            return _first;
        }

        public override ISequence rest()
        {
            return _rest;
        }

        public override ISequence cons(object first)
        {
            return new PersistentList(null, first, this);
        }

        public override XronosObject withMeta(IPersistentMap meta)
        {
            return new PersistentList(meta, _first, _rest);
        }

        #region IPersistentStack Members

        public object peek()
        {
            return first();
        }

        public IPersistentStack pop()
        {
            if (_rest != null)
                return (IPersistentList)((PersistentList)_rest).withMeta(meta());
            return null;
        }

        #endregion

        #region IPersistentCollection Members

        public int count()
        {
            return _count;
        }

        public ISequence seq()
        {
            if (_count == 0)
                return null;
            return this;
        }

        IPersistentCollection IPersistentCollection.cons(object o)
        {
            return new PersistentList(null, o, this);
        }

        public IPersistentCollection empty()
        {
            return Empty;
        }

        #endregion

        #region IReduce Members

        public object reduce(object f)
        {
            var ret = first();
            for (var seq = rest(); seq != null; seq = seq.rest())
                ret = FunctionHelper.Invoke<object>(f, ret, seq.first());
            return ret;
        }

        public object reduce(object f, object start)
        {
            var ret = start;
            for (ISequence seq = this; seq != null; seq = seq.rest())
                ret = FunctionHelper.Invoke<object>(f, ret, seq.first());
            return ret;
        }

        #endregion

        private class EmptyList : IPersistentList, IReduce, ICollection, ISequence
        {
            #region IPersistentStack Members

            public object peek()
            {
                return null;
            }

            public IPersistentStack pop()
            {
                return null;
            }

            #endregion

            #region IPersistentCollection Members

            public int count()
            {
                return 0;
            }

            public ISequence seq()
            {
                return null;
            }

            public IPersistentCollection cons(object o)
            {
                return new PersistentList(null, o, null);
            }

            public IPersistentCollection empty()
            {
                return this;
            }

            #endregion

            #region IReduce Members

            public object reduce(object f)
            {
                return FunctionHelper.Invoke<object>(f);
            }

            public object reduce(object f, object start)
            {
                return start;
            }

            #endregion

            #region ICollection Members

            public void CopyTo(Array array, int index)
            {
                return;
            }

            public int Count
            {
                get { return 0; }
            }

            public bool IsSynchronized
            {
                get { return false; }
            }

            public object SyncRoot
            {
                get { return this; }
            }

            #endregion

            #region IEnumerable Members

            public IEnumerator GetEnumerator()
            {
                return new object[0].GetEnumerator();
            }

            #endregion

            #region ISequence Members

            public object first()
            {
                return null;
            }

            public ISequence rest()
            {
                return null;
            }

            ISequence ISequence.cons(object first)
            {
                return (ISequence)this.cons(first);
            }

            #endregion
        }
    }
}
Back to Top