Ýta

Tools to further your iterator pipelines

Ýta (pronounced /itʰaː/ eat-ah; meaning bulldozer in Icelandic) is an iterable helper library (similar to itertools) designed for pipelines. Every operator is a function that returns a function that consumes a passed in iterable, operate on its iterator and returns another iterable, thus continuing down the pipeline.

Along with operators, this library provides handy generators which return an iterable to start a pipeline, combinators to merge two or more iterables into a single pipeline, and consumers to end the pipeline and return a value.

import { map, pipe, range, reduce } from "yta";

// Sum of the first five squares.
pipe(
  range(1, 6),
  map((n) => n ** 2),
  reduce((sum, square) => sum + square, 0),
);
// => 55

Generators

Generators return an iterable that you can use to start a pipeline.

• flatRepeat (sync, async)
• fromEvent (async)
• of (sync, async)
• range (sync)
• recurrent (sync, async)
• repeat (sync, async)

Combinators

Combinators consume two or more iterables and combine them into a single iterable.

• chain (sync, async)
• zip (sync, async)
• zipLongest (sync, async)

Operators

Operators perform an operation on the items of the iterable, returning a new iterator with new items.

Note that all operators are lazy.

• accumulate (sync, async)
• asAsync (sync)
• aside (sync, async)
• cycle (sync)
• drop (sync, async)
• dropWhile (sync, async)
• enumerate (sync, async)
• filter (sync, async)
• flat (sync, async)
• flatMap (sync, async)
• map (sync, async)
• slice (sync, async)
• take (sync, async)
• takeWhile (sync, async)
• uniqueOn (sync, async)

Consumers

Consumers close the pipeline returning a single value when the iteration has finished.

Note that some consumers (such as groupBy) return a collection of items, such as maps or arrays, which are also iterables and can be pushed down the pipeline. Unlike operators, however, these are not lazy. Meaning the parent iterable needs to finish passing all its items before consumers can push down their first item.

• at (sync, async)
• count (sync, async)
• every (sync, async)
• find (sync, async)
• first (sync, async)
• forEach (sync, async)
• groupBy (sync, async)
• includes (sync, async)
• last (sync, async)
• reduce (sync, async)
• some (sync, async)
• toArray (sync, async)