Variadic custom function in Google Sheets Script

Question

I'd like to accept a variable number of individual cells as arguments into a custom Google Sheets function, eg:

function least(range){
  var res = 100000;
  for (var i = 0; i < range.length; i++){
    if (range[i] < res) res = range[i];
  }
  return res;
}

(I'm aware that returning the minimum value of a list is already built-in; this is an example.)

I'd like to run the function on a sheet with disjoint cells, like so:

=least(A1, A3, A5, B2)

where I am able to use an arbitrary number of arguments.

I have tried using what appears to be JavaScript's variadic argument object , like this:

function least(...range){
    // access elements using range as an array
}

but in this case, I get an error: "Missing formal parameter."

Am I not using the variadic argument correctly, or is it disallowed in Google Scripts, or do they have a house style for this that's different from JavaScript's?

Thanks in advance.

Answer 1

It appears that the object arguments contains any/all variadic function input. I load that object's values into an array at the top of the function like so, and have no trouble from the Google Sheets compiler (and it works on the sheet):

function least(){
    var range = arguments;
    // range now contains all of the arguments supplied to the function
}

Answer 2

I've created this restParam function to solve this issue. I know the question as been ask a long time ago but maybe it can help others

Here's the func:

function restParam(maxParam, args, containerArray) {
  Logger.log("Args length");
  Logger.log(args.length);

  if(args.length > maxParam) {
    for(var i = maxParam -1; i < args.length; i++) {
      Logger.log(args[i])
      containerArray.push(args[i]);
    };

    return containerArray;
  };
};

and heres an example:

//function as 14 params
function foo(address, offset, sale, siring, sorting, breedable, stage, class, pureness, region, title, mystic, num_mystic, parts) {
  var restAr = [];;

  restParam(14, arguments, restAr);

...}

Answer 3

The example you gave is not using the variadic argument object. It's using the rest parameter ([ https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters][1] )

You can use it like a normal array:

function least(...range) {
  var res = Infinity;
  for (var i = 0; i < range.length; i++){
    if (range[i] < res) res = range[i];
  }
  return res;
}

and use it like this

least(1, 2, 3) // -> 1 !