I have a simple arrow function:
const db = (url, type, body?) => ({url, type, body})
and I don't want to return body property if it's an empty db argument.
3 Answers
Ask for the value of body
const db = (url, type, body) => Object.assign({url, type}, (body ? {body} : {}));
console.log(db("Ele", "Stack"));
console.log(db("Ele", "Stack", "mybody"));
Comments
You can do:
const db = (url, type, body) => (body ? {url, type, body} : {url, type})
4 Comments
Maxime Girou
OP didin't give details about the body parameter but i guess it's an object. So you must check the length with Object.keys()
Bergi
@MaximeGirou An empty object is different from "no object" already, you don't need to count its properties for that.
Brent Thierens
It can be anything, it doesn't matter too much. The OP mentioned that if it was not provided, it shouldn't be returned. It it is not provided, body will be undefined and the correct object will be returned. It is true however, that false or an empty body object would return the short object as well
Maxime Girou
it depends on what the OP means when he says 'empty'. if it is an empty object or undefined
You can check this way
const db = (url, type, body) => (Object.keys(body).length > 0 ? { url, type, body } : { url, type })
1 Comment
Brent Thierens
Nobody said body needed to be an object. If it is not passed to the function, a simple undefined check is enough
undefined? That's exactly whatbodyshould become when you want to "omit" it - your code already works!