| /* |
| * |
| * Copyright 2015, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #import <Foundation/Foundation.h> |
| |
| /** |
| * A GRXWriteable is an object to which a sequence of values can be sent. The |
| * sequence finishes with an optional error. |
| */ |
| @protocol GRXWriteable <NSObject> |
| |
| /** Push the next value of the sequence to the receiving object. */ |
| - (void)writeValue:(id)value; |
| |
| /** |
| * Signal that the sequence is completed, or that an error ocurred. After this |
| * message is sent to the instance, neither it nor writeValue: may be |
| * called again. |
| */ |
| - (void)writesFinishedWithError:(NSError *)errorOrNil; |
| @end |
| |
| typedef void (^GRXValueHandler)(id value); |
| typedef void (^GRXCompletionHandler)(NSError *errorOrNil); |
| typedef void (^GRXSingleHandler)(id value, NSError *errorOrNil); |
| typedef void (^GRXEventHandler)(BOOL done, id value, NSError *error); |
| |
| /** |
| * Utility to create objects that conform to the GRXWriteable protocol, from |
| * blocks that handle each of the two methods of the protocol. |
| */ |
| @interface GRXWriteable : NSObject<GRXWriteable> |
| |
| + (instancetype)writeableWithSingleHandler:(GRXSingleHandler)handler; |
| + (instancetype)writeableWithEventHandler:(GRXEventHandler)handler; |
| |
| - (instancetype)initWithValueHandler:(GRXValueHandler)valueHandler |
| completionHandler:(GRXCompletionHandler)completionHandler |
| NS_DESIGNATED_INITIALIZER; |
| @end |