Jorge Canizales | e8304d5 | 2015-02-17 19:50:51 -0800 | [diff] [blame] | 1 | /* |
| 2 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 3 | * Copyright 2015 gRPC authors. |
Jorge Canizales | e8304d5 | 2015-02-17 19:50:51 -0800 | [diff] [blame] | 4 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
Jorge Canizales | e8304d5 | 2015-02-17 19:50:51 -0800 | [diff] [blame] | 8 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
Jorge Canizales | e8304d5 | 2015-02-17 19:50:51 -0800 | [diff] [blame] | 10 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
Jorge Canizales | e8304d5 | 2015-02-17 19:50:51 -0800 | [diff] [blame] | 16 | * |
| 17 | */ |
| 18 | |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 19 | #import <Foundation/Foundation.h> |
| 20 | |
| 21 | #import "GRXWriter.h" |
| 22 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 23 | /** |
| 24 | * Utility to construct GRXWriter instances from values that are immediately available when |
| 25 | * required. |
| 26 | * |
| 27 | * Thread-safety: |
| 28 | * |
| 29 | * An object of this class shouldn't be messaged concurrently by more than one thread. It will start |
| 30 | * messaging the writeable before |startWithWriteable:| returns, in the same thread. That is the |
| 31 | * only place where the writer can be paused or stopped prematurely. |
| 32 | * |
| 33 | * If a paused writer of this class is resumed, it will start messaging the writeable, in the same |
| 34 | * thread, before |setState:| returns. Because the object can't be legally accessed concurrently, |
| 35 | * that's the only place where it can be paused again (or stopped). |
| 36 | */ |
Jorge Canizales | a38baae | 2015-07-16 21:12:56 -0700 | [diff] [blame] | 37 | @interface GRXImmediateWriter : GRXWriter |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 38 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 39 | /** |
| 40 | * Returns a writer that pulls values from the passed NSEnumerator instance and pushes them to |
| 41 | * its writeable. The NSEnumerator is released when it finishes. |
| 42 | */ |
Jorge Canizales | 5604712 | 2015-07-17 12:18:08 -0700 | [diff] [blame] | 43 | + (GRXWriter *)writerWithEnumerator:(NSEnumerator *)enumerator; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 44 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 45 | /** |
| 46 | * Returns a writer that pushes to its writeable the successive values returned by the passed |
| 47 | * block. When the block first returns nil, it is released. |
| 48 | */ |
Muxi Yan | 0c0ebc5 | 2017-10-19 18:41:01 -0700 | [diff] [blame^] | 49 | + (GRXWriter *)writerWithValueSupplier:(id (^)(void))block; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 50 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 51 | /** |
| 52 | * Returns a writer that iterates over the values of the passed container and pushes them to |
| 53 | * its writeable. The container is released when the iteration is over. |
| 54 | * |
| 55 | * Note that the usual speed gain of NSFastEnumeration over NSEnumerator results from not having to |
| 56 | * call one method per element. Because GRXWriteable instances accept values one by one, that speed |
| 57 | * gain doesn't happen here. |
| 58 | */ |
Jorge Canizales | 5604712 | 2015-07-17 12:18:08 -0700 | [diff] [blame] | 59 | + (GRXWriter *)writerWithContainer:(id<NSFastEnumeration>)container; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 60 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 61 | /** |
| 62 | * Returns a writer that sends the passed value to its writeable and then finishes (releasing the |
| 63 | * value). |
| 64 | */ |
Jorge Canizales | 5604712 | 2015-07-17 12:18:08 -0700 | [diff] [blame] | 65 | + (GRXWriter *)writerWithValue:(id)value; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 66 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 67 | /** |
| 68 | * Returns a writer that, as part of its start method, sends the passed error to the writeable |
| 69 | * (then releasing the error). |
| 70 | */ |
Jorge Canizales | 5604712 | 2015-07-17 12:18:08 -0700 | [diff] [blame] | 71 | + (GRXWriter *)writerWithError:(NSError *)error; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 72 | |
Jorge Canizales | b10776c | 2015-10-26 10:44:55 -0700 | [diff] [blame] | 73 | /** |
| 74 | * Returns a writer that, as part of its start method, finishes immediately without sending any |
| 75 | * values to its writeable. |
| 76 | */ |
Jorge Canizales | 5604712 | 2015-07-17 12:18:08 -0700 | [diff] [blame] | 77 | + (GRXWriter *)emptyWriter; |
Jorge Canizales | 30697c9 | 2015-02-17 17:09:14 -0800 | [diff] [blame] | 78 | |
| 79 | @end |