I want to delete object from array by id using Ramda. For example:

const arr = [
  {id: '1', name: 'Armin'},
  {id: '2', name: 'Eren'}, <- delete this object
  {id: '3', name: 'Mikasa'}
];

I want to delete object from array by id using Ramda. For example:

const arr = [
  {id: '1', name: 'Armin'},
  {id: '2', name: 'Eren'}, <- delete this object
  {id: '3', name: 'Mikasa'}
];

• javascript
• functional-programming
• ramda.js

• Have you tried anything? Its a fairly simple operation. – Rajesh Commented Aug 8, 2019 at 10:00
• @Rajesh, sure, I've tried to use R.filter(), R.reject(), but I still new in Ramda – Arthur Commented Aug 8, 2019 at 10:03
• Possible duplicate: stackoverflow.com/questions/29254470/… – Rajesh Commented Aug 8, 2019 at 10:03
• Try R.filter(({ id }) => id !== '2', arr). For more info, refer: ramdajs.com/0.19.1/docs/#filter. Also a pointer, when you ask a question, please share your attempt in question. That makes a requirement, problem and we could help accordingly – Rajesh Commented Aug 8, 2019 at 10:04

4 Answers 4

You can user filter function, with a composed functions propEq & not

const result = filter(
  compose(
   not,
   propEq('id', 2)
  ),
  array,
)
console.log(result)

You can use both filter or reject:

R.reject(o => o.id === '2', arr);

R.filter(o => o.id !== '2', arr);

You can use reject.

The reject() is a complement to the filter(). It excludes elements of a filterable for which the predicate returns true.

let res = R.reject(R.propEq('id', '2'))(arr);

// you could create a generic rejectWhere function
const rejectWhere = (arg, data) => R.reject(R.whereEq(arg), data);


const arr = [
  {id: '1', name: 'Armin'},
  {id: '2', name: 'Eren'}, // <- delete this object
  {id: '3', name: 'Mikasa'}
];


console.log(
  'result', 
  rejectWhere({ id: '2' }, arr),
);

// but also
// rejectWhere({ name: 'Eren' }, arr),

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