RACSignal: how to reduce on arbitrarily large combine - objective-c

Question

Consider an example (paraphrased) from the ReactiveCocoa Introduction, which
enables based on whether the .password and .passwordConfirm text fields match:
RAC(self.enabled) = [RACSignal
combineLatest:#[ RACAble(self.password), RACAble(self.passwordConfirm) ]
reduce:^(NSString *password, NSString *passwordConfirm) {
return #([passwordConfirm isEqualToString:password]);
}];
Here we know at compile time how many and what things we are combining, and it is useful to destructure/map the "combine" array into multiple arguments to the reduce block. What about when that won't work. For instance, if you want:
RAC(self.enabled) = [RACSignal
combineLatest:arrayOfSignals
reduceAll:^(NSArray *signalValues) { // made this up! don't try at home.
// something ...
}];
How do you do this with ReactiveCocoa?
UPDATE: the accepted answer's comments help explain what I was missing.

Answer 1

You can use map:
RAC(self.enabled) = [[RACSignal combineLatest:arrayOfSignals]
map:^(RACTuple *signalValues) {
// something
}
];
A RACTuple can be manipulated in many ways, it conforms NSFastEnumeration, it has the allObjects method and also the rac_sequence method. You can for example combine all boolean values this way:
RAC(self.enabled) = [[RACSignal combineLatest:arrayOfSignals]
map:^(RACTuple *signalValues) {
return #([signalValues.rac_sequence all:^BOOL(NSNumber *value) {
return [value boolValue];
}]);
}
];
Hope it helps.