Counts the number of values.
Similar: index, indexRange, size, isEmpty.
This is part of package extra-array.
array.size(x, [i], [I]);
// x: an array
// i: start index (-ve: from right) (0)
// I: end index (-ve: from right) (X)const array = require("extra-array");
var x = [2, 4, 6, 8];
array.size(x);
// 4
array.size(x, 1);
// 3
array.size(x, 1, 3);
// 2