The Underscore.js _.unary() method returns a new function that accepts only one argument and passes this argument to the given function. Additional arguments are discarded.
Syntax:
_.unary( 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 unary function var gfgFunc = _.unary(fun); console.log( "Arguments are :" , gfgFunc(1, 2, 3)); |
Output:
Arguments are : [Arguments] { '0': 1 }
Example 2:
// Defining underscore contrib variable var _ = require( 'underscore-contrib' ); // Function function fun() { return arguments; } // Making unary function var gfgFunc = _.unary(fun); // Rest arguments are excluded console.log( "Arguments are :" , gfgFunc(1, 2, 3, 4, 5, 6, 7, 8)); |
Output:
Arguments are : [Arguments] { '0': 1 }
Example 3:
// Defining underscore contrib variable var _ = require( 'underscore-contrib' ); // Function function fun(a){ return a; } // Making unary function var gfgFunc = _.unary(fun); // Only one argument is passed console.log( "Best Platform :" , gfgFunc( "neveropen" )); |
Output:
Best Platform : neveropen