JavaScript equivalent of Python's format() function?

Question

Python has this beautiful function to turn this:

bar1 = 'foobar' bar2 = 'jumped' bar3 = 'dog'  foo = 'The lazy ' + bar3 + ' ' + bar2 ' over the ' + bar1 # The lazy dog jumped over the foobar 

Into this:

bar1 = 'foobar' bar2 = 'jumped' bar3 = 'dog'  foo = 'The lazy {} {} over the {}'.format(bar3, bar2, bar1) # The lazy dog jumped over the foobar 

Does JavaScript have such a function? If not, how would I create one which follows the same syntax as Python's implementation?

Answer 1

Another approach, using the String.prototype.replace method, with a "replacer" function as second argument:

String.prototype.format = function () {   var i = 0, args = arguments;   return this.replace(/{}/g, function () {     return typeof args[i] != 'undefined' ? args[i++] : '';   }); };  var bar1 = 'foobar',     bar2 = 'jumped',     bar3 = 'dog';  'The lazy {} {} over the {}'.format(bar3, bar2, bar1); // "The lazy dog jumped over the foobar" 

Answer 2

There is a way, but not exactly using format.

var name = "John";  var age = 19;  var message = `My name is ${name} and I am ${age} years old`;  console.log(message);

jsfiddle - link