if I have:
function foo(number, ...args) {
//foo to add args to sum
}
and I want a caller to be able to call foo like:
foo(10, 1, 2, 3); // 16
or:
foo(10, [1, 2, 3]); //16
The question is how to implement this. Can I do this:
function foo(number, ...args) {
let toAddArr = Array.isArray(args[0]) ? args[0] : args;
for (let toAdd of toAddArr) {
number = number + toAdd;
}
return number;
}
You could use some recursion:
function foo(...args) {
var sum = 0;
args.forEach((arg) => {
if (!Array.isArray(arg))
sum += arg
else
sum += foo(...arg); // if it's an array, destructure
});
return sum;
}
With that code, you can even pass arrays inside arrays inside arrays if you want :)
Edit, with a for loop:
function foo(...args) {
var sum = 0;
for (var arg of args) {
if (!Array.isArray(arg))
sum += arg
else
sum += foo(...arg); // if it's an array, destructure
};
return sum;
}
Well you can convert the arguments to an array and concat them.
function foo(){
return [].concat.apply([],Array.prototype.slice.call(arguments)).reduce( function (p,c) { return p + c; }, 0);
}
var x1 = foo(10, [1,2,3]);
console.log(x1);
var x2 = foo(10,1,2,3);
console.log(x2);
[].slice.call(arguments) instead of Array.prototype.slice.call(arguments)
You can use .concat with .apply, and for sum .reduce, like this
function foo(...args) {
return ([].concat.apply([], args)).reduce(function (prev, curr) {
return prev + curr;
}, 0);
}
for nested arrays recursion might work nicely. You can have only numbers or arrays or nested arrays or mixed.
function add() {
return Array.prototype.reduce.call(arguments, function(p, c) {
if (Array.isArray(c)) {
return p + add.apply(null, c);
} else {
return p + c;
}
});
}
