Mastering Immutable.js

Basic sequence creation

You can create new sequences by passing the Seq() constructor JavaScript arrays or objects, as follows:

import { Seq } from 'immutable';const myIndexedSeq = Seq([1, 2, 3]);const myKeyedSeq = Seq({ one: 1, two: 2, three: 3 });console.log('myIndexedSeq', myIndexedSeq.toJS());// -> myIndexedSeq [ 1, 2, 3 ]console.log('myKeyedSeq', myKeyedSeq.toJS());// -> myKeyedSeq { one: 1, two: 2, three: 3 }

There are actually two types of sequence collections: Seq.Indexed and Seq.Keyed. The Seq() constructor, which is really just a function due to the absence of the new keyword, will return the correct type of collection depending on what's passed to it.

Generally speaking, you don't have to worry about the distinction between indexed ...