TODO

## Compatibility

[] nodejs version
[] brower

## pudding

[] methods `reduce*` returns a prraypromise or prray when initialValue is a prray.
[] methods `reduce*` compatibility

## Features

### Async controls

[] concurrency
[] retries
[] fallback
[] defaults

### Complain of normal array???

[] safely reverse()

### Useful methods???

[] compact

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## Project polish

[x] Add types for all of methods
[x] Add real-world tests
[x] Set ts mode to strict


## Implement methods

[x] Array.prototype.concat()
[x] Array.prototype.copyWithin()
[x] Array.prototype.entries()
[x] Array.prototype.every()
[x] Array.prototype.fill()
[x] Array.prototype.filter()
[x] Array.prototype.find()
[x] Array.prototype.findIndex()
[xx] Array.prototype.flat()
[xx] Array.prototype.flatMap()
[x] Array.prototype.forEach()
[x] Array.prototype.includes()
[x] Array.prototype.indexOf()
[x] Array.prototype.join()
[x] Array.prototype.keys()
[x] Array.prototype.lastIndexOf()
[x] Array.prototype.map()
[x] Array.prototype.pop()
[x] Array.prototype.push()
[x] Array.prototype.reduce()
[x] Array.prototype.reduceRight()
[x] Array.prototype.reverse()
[x] Array.prototype.shift()
[x] Array.prototype.slice()
[x] Array.prototype.some()
[x] Array.prototype.sort()
[x] Array.prototype.splice()
[x] Array.prototype.toLocaleString()
[xx] Array.prototype.toSource()
[x] Array.prototype.toString()
[x] Array.prototype.unshift()
[x] Array.prototype.values()

## Document methods

[x] mapAsync<U>
[x] filterAsync
[x] reduceAsync
[x] reduceRightAsync
[x] sortAsync
[x] findAsync
[x] findIndexAsync
[x] everyAsync
[x] someAsync
[x] forEachAsync
[x] slice
[x] map<U>
[x] filter
[x] find
[x] findIndex
[x] every
[x] some
[x] includes
[x] indexOf
[x] lastIndexOf
[x] join
[x] keys
[x] values
[x] entries
[x] fill
[x] sort
[x] concat
[x] copyWithin
[x] toString
[x] toLocaleString
[x] forEach
[x] pop
[x] push
[x] reverse
[x] reduce
[x] reduceRight
[x] shift
[x] unshift
[x] splice
[x] toArray