Lodash _.pullAllBy() Method

The _.pullAllBy() method is used to remove the values from the original array by iterating over each element in the array by using the Iteratee function. It is almost the same as _.pullAll() function.

Syntax:

_.pullAllBy(array, values, [iteratee=_.identity])

Parameters: This method accepts two parameters as mentioned above and described below:

• array: This parameter holds the array that needs to be modified.
• values: This parameter holds the values in an array that needs to be removed from the first array.
• Iteratee: This is the function that Iteratee over each element.

Return Value: It returns an array.

Note: If the iteratee function is not given then _.pullAllBy() function act as _.pullAll() function.  

Example 1:

Javascript

// Requiring the lodash library
const _ = require("lodash");

// Original array
let array1 = [1, 2, 3, 4.2]

// Array to be subtracted
let val = [2, 3, 3, 5]

// Printing the original array
console.log("Before : ", array1);

// Array after _.pullAllBy()
// method where Math.double is the
// comparable function
_.pullAllBy(array1, val, Math.double);

// Printing the output
console.log("After : ", array1);

Output:

Example 2:

Javascript

// Requiring the lodash library
const _ = require("lodash");

// Original array
let array1 = [1, 2, 3, 4.2]
let array2 = [1, 2, 3, 4.2]

// Value array to be subtracted
let val = [2, 3, 4, 5]

// Printing the original array
console.log("Before : ", array1);

// Array after _.pullAllBy()
// method where Math.double is the
// comparable function
_.pullAllBy(
    array1, val, Math.floor);

// Array after _.pullAllBy function
// where no comparable function is given
 _.pullAllBy(array2, val);

// Printing the output
console.log("When compare funct is given: ",
        array1);

// Printing the output
console.log("When compare funct is not given: ",
        array2);

Output:

Note: This will not work in normal JavaScript because it requires the library lodash to be installed.