Function chain

chain<TIn>(secondIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>): ((firstIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>) => IterableIterator<TIn> | AsyncIterableIterator<TIn>)
Chain the argument iterator after the incoming iterator.

It will also work when one iterator is synchronous and the other one is asynchronous!

Example
```
const chained = pipe(
 itr8Range(1, 3),
 chain(itr8Range(4, 6))
);

// chained yields: 1, 2, 3, 4, 5, 6
```
Returns
An iterator that yields all values from the first iterator, then all values from the second iterator
Type Parameters
- TIn
Parameters
- secondIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>
  
  The iterator to chain after the incoming iterator
Returns ((firstIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>) => IterableIterator<TIn> | AsyncIterableIterator<TIn>)
- - (firstIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>): IterableIterator<TIn> | AsyncIterableIterator<TIn>
  - Parameters
    - firstIterator: Iterator<TIn, any, undefined> | AsyncIterator<TIn, any, undefined>
    Returns IterableIterator<TIn> | AsyncIterableIterator<TIn>
- Defined in operators/general/chain.ts:24