Proper Way to Reference Variables in Javascript

Question

I'm currently refactoring my code and I want to export an object array called REFERENCE_LIST to another file.

reference.js

export const REFERENCE_LIST = [
 {name:"TypeA", foodList:foodAList}, 
 {name:"TypeB", foodList:foodBList}
]

export const foodAList = ['apple', 'orange', 'banana']
];

export const foodBList = ['meat', 'fish']
];

However, the foodList field from REFERENCE_LIST is always "undefined". Am I referencing these arrays incorrectly?

yes the console is right because foodList was never declared or assigned so it remains undefined when you are trying to use it. — Dennisrec
– Dennisrec, Commented May 20, 2017 at 18:56
And the reason why the name field works is because it is a normal string. — Dennisrec
– Dennisrec, Commented May 20, 2017 at 18:58

Bergi · Accepted Answer · 2017-05-20 18:57:56Z

3

You cannot reference variables in JS. You can reference object values, though - but those objects need to be created first for that:

export const foodAList = ['apple', 'orange', 'banana'];
export const foodBList = ['meat', 'fish'];

export const REFERENCE_LIST = [
  {name:"TypeA", foodList:foodAList}, 
  {name:"TypeB", foodList:foodBList}
];

You might also use getters where the order of creation doesn't matter:

export const REFERENCE_LIST = [
  {name:"TypeA", get foodList() { return foodAList; }}, 
  {name:"TypeB", get foodList() { return foodBList; }}
];

But even those will throw an exception when you evaluate them before the constants are initialised.

answered May 20, 2017 at 18:57

Bergi

671k162 gold badges1k silver badges1.5k bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Proper Way to Reference Variables in Javascript

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related