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Decrement by 1, return current

Atomically decrements by one the current value and returns the updated (current) value of the counter. Multiple concurrent client requests are guaranteed to return unique updated value.

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

where:

Argument                Description
counterName name of the counter to decrement.

Example

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

//

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

Codeless Reference

codeless_atomic_counters_decrement_1_return_current

where:

Argument                Description
counter name Name of the counter whose value must be decremented.
return current value When this box is checked, the operation returns the current value of the counter.

Returns the current value of the counter.

Consider the following counter:

codeless_atomic_counters_decrement_1_return_previous_2

The example below decrements the value of the "CarsParkingLot" by 1. This operation returns 9, since the return current value box is checked.

codeless_atomic_counters_decrement_1_return_current_2

The result of this operation will look as shown below after the Codeless logic runs:

codeless_atomic_counters_decrement_1_return_previous_4