Lodash _.tap() Method

Lodash _.tap() method of Sequence in lodash is used to call interceptor. Moreover, the main task of the method is to "tap into" a method chain sequence so that the intermediate results can be modified.

Syntax:

_.tap(value, interceptor);

Parameters:

• value: It is the value to be given to the interceptor.
• interceptor: It is the function to be called.

Return Value:

This method returns the value.

Example 1: In this example, we are printing the array in the console by operating some other function on this with the help of the lodash _.tap() method.

// Requiring lodash library
const _ = require('lodash');

// Calling tap() method
let result = _([5, 6, 7]).tap(function (arr) {

    // Modifying input array using push
    // operation
    arr.push(8);
})
    .value();

// Displays output
console.log(result); 

Output:

[ 5, 6, 7, 8 ]

Example 2: In this example, we are printing the array in the console by operating some other function on this with the help of the lodash _.tap() method.

// Requiring lodash library
const _ = require('lodash');

// Calling tap() method
let result = _(['Geeks', 'for']).tap(function (arr) {

    // Modifying input array using push
    // operation
    arr.push('Geeks');
})
    .value();

// Displays output
console.log(result); 

Output:

[ 'Geeks', 'for', 'Geeks' ]

Example 3: In this example, we are printing the array in the console by operating pop and tail method on this with the help of the lodash _.tap() method.

// Requiring lodash library
const _ = require('lodash');

// Calling tap() method
let result = _(['f', 'g', 'h']).tap(function (arr) {

    // Modifying input array using pop
    // operation
    arr.pop();
})
    .tail()     // Using tail() method
    .value();

// Displays output
console.log(result); 

Output:

[ 'g' ]

Reference: https://lodash.com/docs/4.17.15#tap