takewhile.md

Rx.Observable.prototype.takeWhile(predicate, [thisArg])

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Returns elements from an observable sequence as long as a specified condition is true.

Arguments

1. predicate (Function): A function to test each source element for a condition. The callback is called with the following information:
   1. the value of the element
   2. the index of the element
   3. the Observable object being subscribed
2. [thisArg] (Any): Object to use as this when executing callback.

Returns

(Observable): An observable sequence that contains the elements from the input sequence that occur before the element at which the test no longer passes.

Example