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
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
|
// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
using System.Collections.Generic;
using System.Reactive.Concurrency;
using System.Reactive.Disposables;
using System.Threading;
using System.Linq;
#if !NO_TPL
using System.Reactive.Threading.Tasks;
using System.Threading.Tasks;
#endif
namespace System.Reactive.Linq
{
#if !NO_PERF
using ObservableImpl;
#endif
internal partial class QueryLanguage
{
#region - Create -
public virtual IObservable<TSource> Create<TSource>(Func<IObserver<TSource>, IDisposable> subscribe)
{
return new AnonymousObservable<TSource>(subscribe);
}
public virtual IObservable<TSource> Create<TSource>(Func<IObserver<TSource>, Action> subscribe)
{
return new AnonymousObservable<TSource>(o =>
{
var a = subscribe(o);
return a != null ? Disposable.Create(a) : Disposable.Empty;
});
}
#endregion
#region - CreateAsync -
#if !NO_TPL
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, CancellationToken, Task> subscribeAsync)
{
return new AnonymousObservable<TResult>(observer =>
{
var cancellable = new CancellationDisposable();
var taskObservable = subscribeAsync(observer, cancellable.Token).ToObservable();
var taskCompletionObserver = new AnonymousObserver<Unit>(Stubs<Unit>.Ignore, observer.OnError, observer.OnCompleted);
var subscription = taskObservable.Subscribe(taskCompletionObserver);
return new CompositeDisposable(cancellable, subscription);
});
}
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, Task> subscribeAsync)
{
return Create<TResult>((observer, token) => subscribeAsync(observer));
}
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, CancellationToken, Task<IDisposable>> subscribeAsync)
{
return new AnonymousObservable<TResult>(observer =>
{
var subscription = new SingleAssignmentDisposable();
var cancellable = new CancellationDisposable();
var taskObservable = subscribeAsync(observer, cancellable.Token).ToObservable();
var taskCompletionObserver = new AnonymousObserver<IDisposable>(d => subscription.Disposable = d ?? Disposable.Empty, observer.OnError, Stubs.Nop);
//
// We don't cancel the subscription below *ever* and want to make sure the returned resource gets disposed eventually.
// Notice because we're using the AnonymousObservable<T> type, we get auto-detach behavior for free.
//
taskObservable.Subscribe(taskCompletionObserver);
return new CompositeDisposable(cancellable, subscription);
});
}
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, Task<IDisposable>> subscribeAsync)
{
return Create<TResult>((observer, token) => subscribeAsync(observer));
}
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, CancellationToken, Task<Action>> subscribeAsync)
{
return new AnonymousObservable<TResult>(observer =>
{
var subscription = new SingleAssignmentDisposable();
var cancellable = new CancellationDisposable();
var taskObservable = subscribeAsync(observer, cancellable.Token).ToObservable();
var taskCompletionObserver = new AnonymousObserver<Action>(a => subscription.Disposable = a != null ? Disposable.Create(a) : Disposable.Empty, observer.OnError, Stubs.Nop);
//
// We don't cancel the subscription below *ever* and want to make sure the returned resource eventually gets disposed.
// Notice because we're using the AnonymousObservable<T> type, we get auto-detach behavior for free.
//
taskObservable.Subscribe(taskCompletionObserver);
return new CompositeDisposable(cancellable, subscription);
});
}
public virtual IObservable<TResult> Create<TResult>(Func<IObserver<TResult>, Task<Action>> subscribeAsync)
{
return Create<TResult>((observer, token) => subscribeAsync(observer));
}
#endif
#endregion
#region + Defer +
public virtual IObservable<TValue> Defer<TValue>(Func<IObservable<TValue>> observableFactory)
{
#if !NO_PERF
return new Defer<TValue>(observableFactory);
#else
return new AnonymousObservable<TValue>(observer =>
{
IObservable<TValue> result;
try
{
result = observableFactory();
}
catch (Exception exception)
{
return Throw<TValue>(exception).Subscribe(observer);
}
return result.Subscribe(observer);
});
#endif
}
#endregion
#region + DeferAsync +
#if !NO_TPL
public virtual IObservable<TValue> Defer<TValue>(Func<Task<IObservable<TValue>>> observableFactoryAsync)
{
return Defer(() => StartAsync(observableFactoryAsync).Merge());
}
public virtual IObservable<TValue> Defer<TValue>(Func<CancellationToken, Task<IObservable<TValue>>> observableFactoryAsync)
{
return Defer(() => StartAsync(observableFactoryAsync).Merge());
}
#endif
#endregion
#region + Empty +
public virtual IObservable<TResult> Empty<TResult>()
{
#if !NO_PERF
return new Empty<TResult>(SchedulerDefaults.ConstantTimeOperations);
#else
return Empty_<TResult>(SchedulerDefaults.ConstantTimeOperations);
#endif
}
public virtual IObservable<TResult> Empty<TResult>(IScheduler scheduler)
{
#if !NO_PERF
return new Empty<TResult>(scheduler);
#else
return Empty_<TResult>(scheduler);
#endif
}
#if NO_PERF
private static IObservable<TResult> Empty_<TResult>(IScheduler scheduler)
{
return new AnonymousObservable<TResult>(observer => scheduler.Schedule(observer.OnCompleted));
}
#endif
#endregion
#region + Generate +
public virtual IObservable<TResult> Generate<TState, TResult>(TState initialState, Func<TState, bool> condition, Func<TState, TState> iterate, Func<TState, TResult> resultSelector)
{
#if !NO_PERF
return new Generate<TState, TResult>(initialState, condition, iterate, resultSelector, SchedulerDefaults.Iteration);
#else
return Generate_<TState, TResult>(initialState, condition, iterate, resultSelector, SchedulerDefaults.Iteration);
#endif
}
public virtual IObservable<TResult> Generate<TState, TResult>(TState initialState, Func<TState, bool> condition, Func<TState, TState> iterate, Func<TState, TResult> resultSelector, IScheduler scheduler)
{
#if !NO_PERF
return new Generate<TState, TResult>(initialState, condition, iterate, resultSelector, scheduler);
#else
return Generate_<TState, TResult>(initialState, condition, iterate, resultSelector, scheduler);
#endif
}
#if NO_PERF
private static IObservable<TResult> Generate_<TState, TResult>(TState initialState, Func<TState, bool> condition, Func<TState, TState> iterate, Func<TState, TResult> resultSelector, IScheduler scheduler)
{
return new AnonymousObservable<TResult>(observer =>
{
var state = initialState;
var first = true;
return scheduler.Schedule(self =>
{
var hasResult = false;
var result = default(TResult);
try
{
if (first)
first = false;
else
state = iterate(state);
hasResult = condition(state);
if (hasResult)
result = resultSelector(state);
}
catch (Exception exception)
{
observer.OnError(exception);
return;
}
if (hasResult)
{
observer.OnNext(result);
self();
}
else
observer.OnCompleted();
});
});
}
#endif
#endregion
#region + Never +
public virtual IObservable<TResult> Never<TResult>()
{
#if !NO_PERF
return new Never<TResult>();
#else
return new AnonymousObservable<TResult>(observer => Disposable.Empty);
#endif
}
#endregion
#region + Range +
public virtual IObservable<int> Range(int start, int count)
{
return Range_(start, count, SchedulerDefaults.Iteration);
}
public virtual IObservable<int> Range(int start, int count, IScheduler scheduler)
{
return Range_(start, count, scheduler);
}
private static IObservable<int> Range_(int start, int count, IScheduler scheduler)
{
#if !NO_PERF
return new Range(start, count, scheduler);
#else
return new AnonymousObservable<int>(observer =>
{
return scheduler.Schedule(0, (i, self) =>
{
if (i < count)
{
observer.OnNext(start + i);
self(i + 1);
}
else
observer.OnCompleted();
});
});
#endif
}
#endregion
#region + Repeat +
public virtual IObservable<TResult> Repeat<TResult>(TResult value)
{
#if !NO_PERF
return new Repeat<TResult>(value, null, SchedulerDefaults.Iteration);
#else
return Repeat_(value, SchedulerDefaults.Iteration);
#endif
}
public virtual IObservable<TResult> Repeat<TResult>(TResult value, IScheduler scheduler)
{
#if !NO_PERF
return new Repeat<TResult>(value, null, scheduler);
#else
return Repeat_<TResult>(value, scheduler);
#endif
}
#if NO_PERF
private IObservable<TResult> Repeat_<TResult>(TResult value, IScheduler scheduler)
{
return Return(value, scheduler).Repeat();
}
#endif
public virtual IObservable<TResult> Repeat<TResult>(TResult value, int repeatCount)
{
#if !NO_PERF
return new Repeat<TResult>(value, repeatCount, SchedulerDefaults.Iteration);
#else
return Repeat_(value, repeatCount, SchedulerDefaults.Iteration);
#endif
}
public virtual IObservable<TResult> Repeat<TResult>(TResult value, int repeatCount, IScheduler scheduler)
{
#if !NO_PERF
return new Repeat<TResult>(value, repeatCount, scheduler);
#else
return Repeat_(value, repeatCount, scheduler);
#endif
}
#if NO_PERF
private IObservable<TResult> Repeat_<TResult>(TResult value, int repeatCount, IScheduler scheduler)
{
return Return(value, scheduler).Repeat(repeatCount);
}
#endif
#endregion
#region + Return +
public virtual IObservable<TResult> Return<TResult>(TResult value)
{
#if !NO_PERF
return new Return<TResult>(value, SchedulerDefaults.ConstantTimeOperations);
#else
return Return_<TResult>(value, SchedulerDefaults.ConstantTimeOperations);
#endif
}
public virtual IObservable<TResult> Return<TResult>(TResult value, IScheduler scheduler)
{
#if !NO_PERF
return new Return<TResult>(value, scheduler);
#else
return Return_<TResult>(value, scheduler);
#endif
}
#if NO_PERF
private static IObservable<TResult> Return_<TResult>(TResult value, IScheduler scheduler)
{
return new AnonymousObservable<TResult>(observer =>
scheduler.Schedule(() =>
{
observer.OnNext(value);
observer.OnCompleted();
})
);
}
#endif
#endregion
#region + Throw +
public virtual IObservable<TResult> Throw<TResult>(Exception exception)
{
#if !NO_PERF
return new Throw<TResult>(exception, SchedulerDefaults.ConstantTimeOperations);
#else
return Throw_<TResult>(exception, SchedulerDefaults.ConstantTimeOperations);
#endif
}
public virtual IObservable<TResult> Throw<TResult>(Exception exception, IScheduler scheduler)
{
#if !NO_PERF
return new Throw<TResult>(exception, scheduler);
#else
return Throw_<TResult>(exception, scheduler);
#endif
}
#if NO_PERF
private static IObservable<TResult> Throw_<TResult>(Exception exception, IScheduler scheduler)
{
return new AnonymousObservable<TResult>(observer => scheduler.Schedule(() => observer.OnError(exception)));
}
#endif
#endregion
#region + Using +
public virtual IObservable<TSource> Using<TSource, TResource>(Func<TResource> resourceFactory, Func<TResource, IObservable<TSource>> observableFactory) where TResource : IDisposable
{
#if !NO_PERF
return new Using<TSource, TResource>(resourceFactory, observableFactory);
#else
return new AnonymousObservable<TSource>(observer =>
{
var source = default(IObservable<TSource>);
var disposable = Disposable.Empty;
try
{
var resource = resourceFactory();
if (resource != null)
disposable = resource;
source = observableFactory(resource);
}
catch (Exception exception)
{
return new CompositeDisposable(Throw<TSource>(exception).Subscribe(observer), disposable);
}
return new CompositeDisposable(source.Subscribe(observer), disposable);
});
#endif
}
#endregion
#region - UsingAsync -
#if !NO_TPL
public virtual IObservable<TSource> Using<TSource, TResource>(Func<CancellationToken, Task<TResource>> resourceFactoryAsync, Func<TResource, CancellationToken, Task<IObservable<TSource>>> observableFactoryAsync) where TResource : IDisposable
{
return Observable.FromAsync<TResource>(resourceFactoryAsync)
.SelectMany(resource =>
Observable.Using<TSource, TResource>(
() => resource,
resource_ => Observable.FromAsync<IObservable<TSource>>(ct => observableFactoryAsync(resource_, ct)).Merge()
)
);
}
#endif
#endregion
}
}
|
