How to convert Set to string with space?

Question

I want to convert JavaScript Set to string with space.

For example, if I have a set like:

var foo = new Set();
foo.add('hello');
foo.add('world');
foo.add('JavaScript');

And I'd like to print the string from the set: hello world JavaScript (space between each element).

I tried below codes but they are not working:

foo.toString(); // Not working
String(foo); // Not working

Is there simplest and easiest way to convert from Set to string?

score 185 · Accepted Answer · edited Jul 21 '18 at 14:55

185

You can use Array.from:

Array.from(foo).join(' ')

or the spread syntax:

[...foo].join(' ')

edited Jul 21 '18 at 14:55

isanae

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answered Nov 11 '17 at 21:58

Mihai Alexandru-Ionut

47,092
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Array.from is not supported by internet Explorer, if someone has to maintain the compatibility of its script, any other suggestion? – Simona Adriani Nov 26 '18 at 16:09
3

`Array.from` is significantly faster in large sets, though. – Bence László Apr 29 '20 at 13:36
Use a polyfill @SimonaAdriani – Clio Orgyán May 14 '22 at 19:02
1

[Speed comparisons](https://jsbench.me/o1ld6am6ze/1) – robere2 Jan 21 '23 at 18:40

score 0 · Answer 2 · answered Dec 25 '19 at 05:15

You can iterate through the set and build an array of the elements and return the desired string by joining the array.

var foo = new Set();
foo.add('hello');
foo.add('world');
foo.add('JavaScript');
let strArray = [];

for(str of foo){
  strArray.push(str);
}

console.log(strArray.join(" "));

How to convert Set to string with space?

2 Answers2

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