Lodash _.flatMapDeep() Method
Lodash _.flatMapDeep() method creates a flattened array of values by running each element in the given collection through the iteratee function and recursively flattens the mapped results. It is similar to the _.flatMap() method.
Syntax:
_.flatMapDeep(collection, iteratee);
Parameters:
- collection: It is the collection to iterate over.
- iteratee: It is the function that is invoked per iteration.
Return Value:
This method returns the new flattened array.
Example 1: In this example, we are using the _.flatMapDeep() method for duplicating the elements of a given array.
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array let users = ([ 'aaa' , 'bbb' , 'ccc' , 'ddd' , 'eee' , 'fff' ]); // Using the _.flatMapDeep() method let flat_map = _.flatMapDeep(users, function duplicate(n) { return [[[n, n]]]; } ) // Printing the output console.log(flat_map); |
Output:
[
'aaa', 'aaa', 'bbb', 'bbb',
'ccc', 'ccc', 'ddd', 'ddd',
'eee', 'eee'
]
Example 2: In this example, we are using the _.flatMapDeep() method for naking apatter of a given array.
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array let user1 = ([1, 2, 3, 4, 5, 6, 7]); let user2 = ([ 'a' , 'b' , 'c' , 'd' , 'e' ]); // Using the _.flatMapDeep() method let flat_map1 = _.flatMapDeep(user1, function makePattern(n) { return [[[n, n + ">" ]]]; } ) let flat_map2 = _.flatMapDeep(user2, function makePattern(n) { return [[[ "<" + n, n]]]; } ) // Printing the output console.log(flat_map1); console.log(flat_map2); |
Output:
[
1, '1>', 2, '2>',
3, '3>', 4, '4>',
5, '5>', 6, '6>',
7, '7>'
]
[
'<a', 'a', '<b',
'b', '<c', 'c',
'<d', 'd', '<e',
'e'
]