What does '=>' imply in typescript/javascript?

Question

So I have saw tons of '=>' in some code I found online. Can anyone explain to me like I'm 5?

(I am looking for code, and I will post it here once I find it)..

Got it:

            var directive = () =>
        {
            return new MyDirective();
        };

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions Google is your friend here. — CollinD, Oct 31 '15 at 07:49
TypeScript arrow functions : https://basarat.gitbooks.io/typescript/content/docs/arrow-functions.html — basarat, Nov 03 '15 at 22:42

prasun · Answer 1 · 2015-10-31T07:52:07.597

3

this is ECMASCRIPT 6 standard arrow function.

In this case directive is assigned a function with 0 arguments and one return statement

Details are documented here in MDN Docs

edited Oct 31 '15 at 07:52

answered Oct 31 '15 at 07:51

prasun

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Thanks! That clarified everything ;) – uksz Oct 31 '15 at 07:52
The context is `TypeScript` ;) But nevertheless it is correct. – Thomas Junk Oct 31 '15 at 07:55
TypeScript is for js and very similar – prasun Oct 31 '15 at 07:57

Thomas Junk · Accepted Answer · 2015-10-31T08:07:18.113

1

()=> is simply a lambda function, which (in this case) means nothing more than a shorthand notation for a function without a name taking 0 paramaters.

You could have written var directive=function(){return new MyDirective();};

Take a look at John Papas blog Post.

edited Oct 31 '15 at 08:07

answered Oct 31 '15 at 07:53

Thomas Junk

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What does '=>' imply in typescript/javascript?

2 Answers2