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Decrement by 1, return previous

Atomically decrements by one the current value and returns the previous value of the counter. It is possible that multiple concurrent client requests may receive the same previous value. This occurs since only the decrementing part of the logic is atomic, the retrieval of the value before it is decremented is not.

- (void)getAndDecrementWithCounterName:(NSString * _Nonnull)counterName responseHandler:^(NSInteger)responseHandler errorHandler:^(Fault * _Nonnull)errorHandler;
func getAndDecrement(counterName: String, responseHandler: ((Int) -> Void)!, errorHandler: ((Fault) -> Void)!)

where:

Argument                Description
counterName name of the counter to decrement.

Example

[Backendless.shared.counters getAndDecrementWithCounterName:@"MyCounter" responseHandler:^(NSInteger value) {
    NSLog(@"Previous value = %li", value);
} errorHandler:^(Fault *fault) {
    NSLog(@"Error: %@", fault.message);
}];

//

id<IAtomic> myCounter = [Backendless.shared.counters ofCounterName:@"MyCounter"];
[myCounter getAndDecrementWithResponseHandler:^(NSInteger value) {
    NSLog(@"Previous value = %li", value);
} errorHandler:^(Fault *fault) {
    NSLog(@"Error: %@", fault.message);
}];
Backendless.shared.counters.getAndDecrement(counterName: "MyCounter", responseHandler: { value in
    print("Previous value = \(value)")
}, errorHandler: { fault in
    print("Error: \(fault.message ?? "")")
})

//

let myCounter = Backendless.shared.counters.of(counterName: "MyCounter")
myCounter.getAndDecrement(responseHandler: { value in
    print("Previous value = \(value)")
}, errorHandler: { fault in
    print("Error: \(fault.message ?? "")")
})