Mastering Immutable.js

Lazy duplicate removal

What if you have large collections in your application? The ability to execute lazily is key to Immutable.js being able to scale. Using sets to lazily remove duplicates from a collection isn't so simple. Let's give it a shot:

const myList = List.of(  Map.of('one', 1, 'two', 2),  Map.of('three', 3, 'four', 4),  Map.of('one', 1, 'two', 2),  Map.of('five', 5, 'six', 6),  Map.of('one', 1, 'two', 2));myList  .toSetSeq()  .map(v => v.toJS())  .forEach(v => console.log('toSetSeq()', v));  // -> toSetSeq() { one: 1, two: 2 }  // -> toSetSeq() { three: 3, four: 4 }  // -> toSetSeq() { one: 1, two: 2 }  // -> toSetSeq() { five: 5, six: 6 }  // -> toSetSeq() { one: 1, two: 2 }

This didn't work as expected. We used toSetSeq() to convert myList ...