Documentation / @eventkit/base / concatMap

Function: concatMap()

function concatMap<T, O>(predicate): OperatorFunction<T, ObservedValueOf<O>>

Applies a predicate function to each value yielded by the source observable, which returns a different observable that will be merged in a serialized fashion, waiting for each one to complete before subscribing to the next.

Note: If the source observable emits observables quickly and endlessly, and the inner observables it emits generally complete slower than the source emits, you can run into memory issues as the incoming observables collect in an unbounded buffer.

Note: concatMap is equivalent to mergeMap with the concurrency parameter set to 1.

Type Parameters

Type Parameter
T
O extends AsyncObservableInput<any>

Parameters

Parameter	Type
predicate	(value, index) => O

Returns

OperatorFunction<T, ObservedValueOf<O>>