What is the difference of “take” operator's sequence in a chain
For example,
let observable1 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.take(1)
.flatMap{_ in
doSomething()
}
let observable2 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.flatMap{_ in
doSomething()
}
.take(1)
my question is, what is the difference of this two Observable?
They looks same.
ios rx-swift reactivex
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
add a comment |
For example,
let observable1 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.take(1)
.flatMap{_ in
doSomething()
}
let observable2 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.flatMap{_ in
doSomething()
}
.take(1)
my question is, what is the difference of this two Observable?
They looks same.
ios rx-swift reactivex
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
add a comment |
For example,
let observable1 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.take(1)
.flatMap{_ in
doSomething()
}
let observable2 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.flatMap{_ in
doSomething()
}
.take(1)
my question is, what is the difference of this two Observable?
They looks same.
ios rx-swift reactivex
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
For example,
let observable1 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.take(1)
.flatMap{_ in
doSomething()
}
let observable2 = Observable<Void>.of([1, 2, 3, 4, 5, 6, 7])
.flatMap{_ in
doSomething()
}
.take(1)
my question is, what is the difference of this two Observable?
They looks same.
ios rx-swift reactivex
ios rx-swift reactivex
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
asked Nov 21 '18 at 9:15
Mike LuMike Lu
266
266
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
If upstream (observable1/observable2) emits N items, .flatMap() operator emits M items , where M can be greater (usually), lesser or equal to N.
In your 1st example you are taking 1 item from the N items of the upstream. In the 2nd example you are taking 1 item from the the M items emitted by .flatMap() operator.
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
If upstream (observable1/observable2) emits N items, .flatMap() operator emits M items , where M can be greater (usually), lesser or equal to N.
In your 1st example you are taking 1 item from the N items of the upstream. In the 2nd example you are taking 1 item from the the M items emitted by .flatMap() operator.
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
add a comment |
If upstream (observable1/observable2) emits N items, .flatMap() operator emits M items , where M can be greater (usually), lesser or equal to N.
In your 1st example you are taking 1 item from the N items of the upstream. In the 2nd example you are taking 1 item from the the M items emitted by .flatMap() operator.
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
add a comment |
If upstream (observable1/observable2) emits N items, .flatMap() operator emits M items , where M can be greater (usually), lesser or equal to N.
In your 1st example you are taking 1 item from the N items of the upstream. In the 2nd example you are taking 1 item from the the M items emitted by .flatMap() operator.
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
If upstream (observable1/observable2) emits N items, .flatMap() operator emits M items , where M can be greater (usually), lesser or equal to N.
In your 1st example you are taking 1 item from the N items of the upstream. In the 2nd example you are taking 1 item from the the M items emitted by .flatMap() operator.
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
answered Nov 21 '18 at 9:31
Maxim VolginMaxim Volgin
2,0131320
2,0131320
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
add a comment |
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
1
1
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
True, the first example can emit more than one item. The second example can't.
– Daniel T.
Nov 22 '18 at 0:38
add a comment |
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