I've just met with a very interesting task to solve, but I can't do it myself.
Make a function which do the following input!
console.log(foo(4)(5)(6)); // output: 120
The solution is not this:
function foo(number1,number2,number3){
return number1 * number2 * number3;
}
In theory it has to use nested functions.
It is called currying. You need to return function which it's case returns a function which returns the total. Here we also use a term called closure.
function foo(a){
return function(b) {
return function(c){
return a * b * c;
}
}
}
console.log(foo(4)(5)(6));With ES6 syntax
var foo = a => b => c => a*b*c;
console.log(foo(4)(5)(6));For infinite levels you can do
function foo(value){
infinite.total = value;
function infinite(val) {
infinite.total *= val;
return infinite;
}
infinite.toString = function() { return infinite.total; }
return infinite;
}
console.log(foo(4)(5)(6)(7));
var total = foo(4)(5)(6)(7);
console.log(total);But this will output the total in that cases, when toString() is called explicitly or implicitly
currying !
You could use an approach for any length of repeated calls of the function with returning a function and an implementation of toString method.
var foo = function(value) {
function fn(a) {
fn.value *= a;
return fn;
}
fn.value = value;
fn.toString = function () { return fn.value; };
return fn;
}
console.log(foo(4)(5)(6));
console.log(foo(42));
console.log(foo(42)(44));try with currying:
function foo(number) {
return function(number2) {
return function(number3) {
return number * number2 number3;
}
}
}
console.log(foo(5)(6)(7));
https://jsfiddle.net/mv9bm3tL/1/
More information : https://www.sitepoint.com/currying-in-functional-javascript/
You need nested functions - currying;
console.log(foo(4)(5)(6)); // output: 120
let first = foo(4);
let second = first(5);
let last = second(6);
console.log(last);
function foo(number1,number2,number3){
return function(number2){
return function(number3){
return number1 * number2 * number3;
}
}
}
Closures in javascript will help you to achieve this.
function foo(a){
return function(b){
return function(c){
return a*b*c;
}
}
}
console.log(foo(4)(5)(6)); //will return 120
Using arrow functions;
var foo = a => b => c => a*b*c;
console.log(foo(4)(5)(6));