is-iterator-like

Use duck typing to check whether a Javascript object has the form of an ES6 iterator

Install

npm install --save is-iterator-like

Explanation

This uses simple duck-typing methods to check whether a value comes in the form of an iterator - anything with a "next" property that can be called as a function. It isn't a sure-fire test whether a value truly implements iterator protocol, which can't be done reliably; the only way to know that for sure is to use it as an iterator. However, this method is suitable for tests, or to catch any blatantly incorrect inputs that you expect to be iterators.

Usage

var isIteratorLike = require('is-iterator-like');
var xd = require('transducers.js');

var iter = xd.iterator({a: 1, b: 2, c: 3});

isIteratorLike(iter); // true
isIteratorLike('foo'); // false
isIteratorLike(undefined); // false