Deprecation Guide for Deprecate import readOnly from @ember/object/computed

readOnly from @ember/object/computed is deprecated.

Migration

Use a getter that returns the underlying value.

Before:

import { readOnly } from '@ember/object/computed';
class Person {
  firstName = 'Tom';
  @readOnly('firstName') givenName;
}

After:

class Person {
  firstName = 'Tom';
  get givenName() { return this.firstName; }
}

Don't define a setter to keep it effectively read-only.