Adding Signal update(f: T? -> T) about interstellar HOT 5 CLOSED

Can you give me an example how you're using this function? I'm not sure what's the use case actually.

from interstellar.

sure.
e.g.: when there is a signal containing a tuple, it provides me a possibility to update the value while
having access to the previous value.

var tupleSignal: Signal<(String, String)> = Signal("a", "b")

func updateFirst(string: String){
    tupleSignal.update {
      (string, $0!.1)
    }
}

from interstellar.

Wouldn't it be easier to just merge two signals in that case?

let a = Signal("a")
let b = Signal("b")
let tupleSignal = a.merge(b)

a.update("some new value") // tupleSignal now contains ("some new value", "b")

from interstellar.

in case I need to be able to observe both on their own? sure.
but this way it is possible to save those extra signals.
so there is only 1 instead of 3.
e.g. I am using it for sort and filter of data sources, where I can easily forget about the individual signals.
no worries if you don't see the use case. I can easily live on w/ an extension.
:-)

from interstellar.

The problem with your implementation is, that it will crash if one of the values becomes an error.

Handling tuples/merging signals is still not completely thought through, so I'm open to suggestions (see #16).

from interstellar.