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Sort by field

importance: 5

We’ve got an array of objects to sort:

let users = [
  { name: "John", age: 20, surname: "Johnson" },
  { name: "Pete", age: 18, surname: "Peterson" },
  { name: "Ann", age: 19, surname: "Hathaway" }
];

The usual way to do that would be:

// by name (Ann, John, Pete)
users.sort((a, b) => a.name > b.name ? 1 : -1);

// by age (Pete, Ann, John)
users.sort((a, b) => a.age > b.age ? 1 : -1);

Can we make it even less verbose, like this?

users.sort(byField('name'));
users.sort(byField('age'));

So, instead of writing a function, just put byField(fieldName).

Write the function byField that can be used for that.

let users = [
  { name: "John", age: 20, surname: "Johnson" },
  { name: "Pete", age: 18, surname: "Peterson" },
  { name: "Ann", age: 19, surname: "Hathaway" }
];

function byField(field) {
  return (a, b) => a[field] > b[field] ? 1 : -1;
}

users.sort(byField('name'));
users.forEach(user => alert(user.name)); // Ann, John, Pete

users.sort(byField('age'));
users.forEach(user => alert(user.name)); // Pete, Ann, John