Collectives™ on Stack Overflow

Find centralized, trusted content and collaborate around the technologies you use most.

Learn more about Collectives

Teams

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

Learn more about Teams return <div> {/* I want to do the equivalent of this: */} {Object.keys(myMap).map(key => <p>{key}: {myMap.get(key)}</p>)} </div>;

This might be a simple question, but I didn't find how to do that, apart from converting myMap to a normal JS object with toJs() , which I don't want to do.

Googling didn't help much with map, Map, object... keywords.

according to the map spec and mobx documentation: https://mobx.js.org/refguide/map.html

you can call the .keys() directly on the map:

{myMap.keys().map(key => <p>{key}: {myMap.get(key)}</p>)}
Edit: excuse me i didn't realise iterator doesnt contain map function. You can make your own: 
Solution
You can create your own iterator map function: 
var x = new Map();
x.set('test','asdf')
console.log(map(x.keys(),(x) => 'prefix:'+x ))
function map(iterator, mapFn){
  var result = [];
  for(var item of iterator){
    result.push(mapFn(item)); 
  return result;
another solution is turing iterator into array:
Array.from(map.keys()).map(...) // array map function of all keys.
hacky prototype method
You can make an extension method in a bit of hacky way, probably does not work for all browsers!:
//Warning this hacky way:
var t = new Map();
t.keys().__proto__.map = function(mapFn){
  return map(this, mapFn);
t.keys().map(x=> x) // now usable!
                Removed the -1 and put a +1. But I didn't accept this answer, because it stills seems a lot of work for something simple. I even prefer the Object.keys(toJs(myMap)).map(...) solutioj
– jeanpaul62
                May 3, 2018 at 9:48
                @amaurymartiny Object.keys => on map is just map.keys() you can do though: Array.from(map.keys()).map(...)
– Joel Harkes
                May 3, 2018 at 9:50
        
Thanks for contributing an answer to Stack Overflow!
Please be sure to answer the question. Provide details and share your research!
But avoid …
Asking for help, clarification, or responding to other answers.
Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.