Underscore.js is a JavaScript library that makes operations on arrays, string, objects much easier and handy. The _.constant() function is used to create a function that returns the parameter given to it. It is almost same as _.identity() function.
Note: It is very necessary to link the underscore CDN before going and using underscore functions in the browser. When linking the underscore.js CDN, the “_” is attached to the browser as global variable.
Syntax:
_.constant( object );
Parameters: This function accepts single parameter object.
Return Value: This function returns the parameter as given to the function.
Below examples illustrate the _.constant() function in Underscore.js:
Example 1:
<!DOCTYPE html> <html> <head> <script src= </script> </head> <body> <script> let str = "neveropen" // _.constant function of underscore.js let strFunc = _.constant(str); console.log(`original str is: ${str}`) console.log(`str Function is: ${strFunc}`) // This will return true console.log(str === strFunc()) // Both strings are exactly same console.log("from str : ", str, " from strFunc: ", strFunc()); </script> </body> </html> |
Output:
Example 2:
<!DOCTYPE html> <html> <head> <script src= </script> </head> <body> <script> // Creating a object let obj = { "a": "one", "b": "two", "c": "three" } // _.constant function of underscore.js let objFunc = _.constant(obj); console.log(`original object is: ${obj}`) console.log(`object Function is: ${objFunc}`) // This will return true console.log(obj === objFunc()) // Both objects are exactly same console.log("from obj : ", obj.a, " from objFunc: ", objFunc().a); // Made Changes in object obj.a = 12 // Change in one object reflects // in another console.log("change in one object " + "reflects in another =>") console.log("from obj : ", obj.a, " from objFunc: ", objFunc().a); </script> </body> </html> |
Output:
Whether you’re preparing for your first job interview or aiming to upskill in this ever-evolving tech landscape, neveropen Courses are your key to success. We provide top-quality content at affordable prices, all geared towards accelerating your growth in a time-bound manner. Join the millions we’ve already empowered, and we’re here to do the same for you. Don’t miss out – check it out now!
