Lodash

map

Collection
since 0.1.0

Arguments

  • Array|Object The collection to iterate over.
  • Function The function invoked per iteration.

Returns

Array the new mapped array.

Creates an array of values by running each element in collection thru iteratee. The iteratee is invoked with three arguments: (value, index|key, collection).

Many lodash methods are guarded to work as iteratees for methods like _.every, _.filter, _.map, _.mapValues, _.reject, and _.some.

The guarded methods are: ary, chunk, curry, curryRight, drop, dropRight, every, fill, invert, parseInt, random, range, rangeRight, repeat, sampleSize, slice, some, sortBy, split, take, takeRight, template, trim, trimEnd, trimStart, and words

Example of Lodash _.map

function square(n) {
  return n * n;
}

_.map([4, 8], square);
// => [16, 64]

_.map({ 'a': 4, 'b': 8 }, square);
// => [16, 64] (iteration order is not guaranteed)

var users = [
  { 'user': 'barney' },
  { 'user': 'fred' }
];

// The `_.property` iteratee shorthand.
_.map(users, 'user');
// => ['barney', 'fred']