javascript - lodash filter on key with multiple values

Question

I am trying to find out in lodash javascript library, how to find out filter array of objects multiple values of key. something similar to SQL - WHERE KEY in (val1, val2)

Having said, with following example :

var?users?=?[
   {?'user':?'barney',?'age':?36,?'active':?true?},
 ??{?'user':?'fred',???'age':?40,?'active':?false?},
   {?'user':?'Avding',???'age':?34,?'active':?true?}
];

_.filter(...)

How can I find users, who's age in (34, 36) ?? numbers can also change runtime

Answer 1

Lodash's filter accepts a predicate. You can create the predicate using partial application, so you can change the values easily:

var users = [
   { 'user': 'barney', 'age': 36, 'active': true },
   { 'user': 'fred',   'age': 40, 'active': false },
   { 'user': 'Avding',   'age': 34, 'active': true }
];

var predicate = function(start, end) {
  return function(user) {
    return _.inRange(user.age, start, end + 1);
  }
}

var result = _.filter(users, predicate(34, 36));

console.log('inRange', result);

/** is equal predicate **/

var predicate = function() {
  var args = _.toArray(arguments);
  
  return function(user) {
    var equalToUserAge = _.partial(_.isEqual, user.age);
    
    return args.some(equalToUserAge);
  }
}

var result = _.filter(users, predicate(34, 40));

console.log('equals', result);

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