Underscore.js _.quaternary() Method

The Underscore.js _.quaternary() returns a new function that accepts only four arguments and passes these arguments to the given function. Additional arguments are discarded.

Syntax:

_.quaternary( fun )

Parameters: This method takes a single parameter as listed above and discussed below:

• fun: This is the given function passed as parameter.

Return Value: This method returns a new function.

Note: To execute the below examples, you have to install the underscore-contrib library by using this command prompt and execute the following command.

npm install underscore-contrib

Example 1: 

// Defining underscore contrib variable
var _ = require('underscore-contrib');

// Function
function fun() {
    return arguments;
}

// Making quaternary function
var gfgFunc = _.quaternary(fun);

console.log("Arguments are :", gfgFunc(1, 2, 3, 4));

Output:

Arguments are : [Arguments] { '0': 1, '1': 2, '2': 3, '3': 4 }

Example 2: In this example, we will add arguments but only the first 4 arguments will be using this method.

// Defining underscore contrib variable
var _ = require('underscore-contrib');

// Function
function add() {
    s = 0
    for(i = 0; i < 4; i++) {
        s += arguments[i]
    }

    return s;
}

// Making quaternary function
var gfgFunc = _.quaternary(add);

// Rest arguments are excluded
console.log("Sum of first 4 arguments is :",
gfgFunc(1, 2, 3, 4, 5, 6, 7));

Output: 

Sum of first 4 arguments is : 10