polyethylene.polyasynciterable.md

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PolyAsyncIterable class

An AsyncIterable<T> with a suite of methods for transforming the iteration into other iterations or to get a single result from it.

This class works as an async version of PolySyncIterable, but all methods accept async function where possible and will always return either PolyAsyncIterables or a Promise to a value.

Signature:

export default class PolyAsyncIterable<T> implements AsyncIterable<T> 

Implements: AsyncIterable<T>

Remarks

The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the PolyAsyncIterable class.

Methods

Method	Modifiers	Description
[Symbol.asyncIterator]()		Allows this class to work as a regular AsyncIterable<T>
append(other)		Return a new iteration that will iterate over this, then over other.
async()		Return this.
chunk(num)		Return an iteration of arrays of size num (except possibly the last) containing groupings of elements of this iteration.
chunkWhile(func)		Return an iteration of arrays with elements of this separated based on the result of calling func(elements).
complete()		Perform this iteration doing nothing.
concat(other)		Return a new iteration that will iterate over this, then over other.
drop(num)		Return a new iteration that skips the first num elements. If there were less than num elements in the iteration, no elements are yielded.
dropLast(num)		Return a new iteration that skips the last num elements. If there were less than num elements in the iteration, no elements are yielded.
dropWhile(func)		Return a new iteration that skips the first few elements for which func(element) returns true.
every(func)		Returns true if calling func(element) returns true for every element, and false otherwise
filter(func)		Return an iteration of the elements of this for which func(element) returns true.
filter(func)		Return an iteration of the elements of this for which func(element) returns true.
filterNotNullish()		Return an iteration of all the elements as this that aren't null or undefined.
find(func)		Returns the first element for which func(element) returns true, or undefined if it never does.
find(func)		Returns the first element for which func(element) returns true, or undefined if it never does.
flat(this)		Return an iteration of the yielded elements of the sub-iterables.
flatMap(func)		Return an iteration of elements of the sub-iterables that result from calling func(element) for every element in this.
flatten(this)		Return an iteration of the yielded elements of the sub-iterables.
forEach(func)		Call a function for each element of this iteration.
groupBy(func)		Return an iteration of group pairs, where the first element is a _group key_ and the second is an iterable of all the elements for which func(element) returned the key.
includes(obj)		Returns whether an element is present in this iteration.
join(glue)		Return the result of joining the elements of this with the given glue, or ',' if no glue is given.
map(func)		Return an iteration of the result of calling func(element) for every element in this.
prefetch()		Return the same iteration, but with its elements requested with anticipation to allow for asynchronous operations to begin and reduce wait times.
prepend(other)		Return a new iteration that will iterate over other, then over this.
reduce(reducer, init)		Returns the result of calling the passed reducer for all elements of the iteration and the result of the previous call to reducer, starting by passing init or, if not present, the first element of the iteration.
reduce(reducer, init)		Returns the result of calling the passed reducer for all elements of the iteration and the result of the previous call to reducer, starting by passing init.
reverse()		Return an iteration of the elements of this in reverse order.
slice(start, end)		Return a new iteration that starts from the startth element (included) and ends at the endth element (excluded) of this.
some(func)		Returns true if calling func(element) returns true for at least one element, and false otherwise
sort(func)		Return an iteration of the elements of this sorted according to func
take(num)		Return a new iteration that iterates only over the first num elements. If there were less than than num elements in the iteration, all elements are yielded with no additions.
takeLast(num)		Return a new iteration that iterates only over the last num elements. If there were less than than num elements in the iteration, all elements are yielded with no additions.
takeWhile(func)		Return a new iteration that yields the first few elements for which func(element) returns true.
tap(func)		Return an iteration of the same elements as this after calling func(element) for all elements.
toArray()		Return an array of all elements of this iteration in the same order that were yielded.
toMap(this)		Return a Map made from the entries of this. This method is roughly equivalent to calling new Map(iter.toArray()).
toObject(this)		Return an object made from the entries of this. This method is roughly equivalent to calling Object.fromEntires(iter.toArray()).
toPartitionArrays(func)		Splits this iteration into two arrays, one with elements for which func(element) returns true (the _truthy elements_) and one for which it returns false (the _falsy elements_).
toPartitionArrays(func)		Splits this iteration into two arrays, one with elements for which func(element) returns true (the _truthy elements_) and one for which it returns false (the _falsy elements_).
unique(func)		Return an iteration of unique elements, where two elements are considered equal if the result of func(element) is the same for both elements.