peekable-array-iterator v1.0.0

Peekable Array Iterator

This module allows iterating over an array (or any other object with an [] accessor and a length attribute, like a string for example) and creates an iterator for peeking at each iteration step.

Example

const PeekableArrayIterator = require('peekable-array-iterator')

const it = new PeekableArrayIterator('HelloWorld')

console.log(it.next().value) // prints 'H'
console.log(it.next().value) // prints 'e'

console.log(it.peek.next().value) // prints 'l'
console.log(it.peek.next().value) // prints 'l'
console.log(it.peek.next().value) // prints 'o'

console.log(it.next().value) // prints 'l'
console.log(it.next().value) // prints 'l'

for (const peek of it.peek) {
  console.log(peek) 
  // prints 'oWorld' in seperate lines
}

API

const it = new PeekableArrayIterator(container, [start])

This creates a new iterator with the container to be iterated over (any object with an [] accessor and a length attribute, like an array or a string). Optionally, a start value can be passed to set the starting index. The starting index is 0 by default. The iterator (aswell, as the peek iterator) uses the standard interface for iterators https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Iterators_and_Generators. This is allows the usage in for-of loops.

it.next()

Return next entry. The returned object has the following form:

  {
    data: The next value
    done: `true`, until there is no next value available
  }

it.peek

Iterator starting at the current index.

it.peek.next()

Same as it.next(), but won't modify the state of it.