JavaScript helper functions calling eachother

Question

I have a collection of helper-functions, like this:

var myHelpers = {

    addFoo: ( name ) => {
        return name + 'foo';
    },

    addFooBar: ( name ) => {
        return this.addFoo( name ) + 'bar'; // This is what throws the error.
    }

}

window.myHelpers = myHelpers;
export default myHelpers;

And I then use it like this:

import myHelpers from "./myHelpers";

let test = 'abc';
test = myHelpers.addFooBar( test );

But this throws the error: Uncaught TypeError: Cannot read properties of undefined

... How do I make these functions call eachother, without getting this error?

_Use a regular function instead of an arrow function..._ Can you please explain why? @Reyno — B001ᛦ, Oct 28 '21 at 13:53
@B001ᛦ There is a duplicate answer which explains this very well. But here is an (extremely short) explanation: normal functions redefine `this` while arrow functions do not — Reyno, Oct 28 '21 at 14:02

score 1 · Accepted Answer · answered Oct 28 '21 at 13:47

1

Use myHelpers instead of this

addFooBar: name => {
  return myHelpers.addFoo(name) + 'bar'
},

answered Oct 28 '21 at 13:47

aerial

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JavaScript helper functions calling eachother

1 Answers1