es6-map – Make Me Engineer

Using Array objects as key for ES6 Map

November 3, 2022 by Tarik

Understand that ES2015 Map keys are compared (almost) as if with the === operator. Two array instances, even if they contain the same values, do not ever compare as === to each other. Try this: var a = new Map(), key = [‘x’, ‘y’]; a.set(key, 1); console.log(a.get(key)); Since the Map class is intended to be … Read more

Typescript: How can I make entries in an ES6 Map based on an object key/value type

July 23, 2022 by Tarik

Here’s the closest I can imagine getting, although I still don’t understand why we don’t just use plain objects to begin with: type ObjectToEntries<O extends object> = { [K in keyof O]: [K, O[K]] }[keyof O] interface ObjectMap<O extends object> { forEach(callbackfn: <K extends keyof O>( value: O[K], key: K, map: ObjectMap<O> ) => void, … Read more