JSFiddle - React, Tailwind, and code Playground

by brigand

JavaScript

Array.prototype.flat = function(depth) {
    depth = Math.floor(depth) || 1;
    var flattend = [];
    !(function flat(array, depth) {
      array.forEach(function(el) {
        if (Array.isArray(el) && depth > 0) {
          flat(el, depth - 1); 
        } else flattend.push(el);
      });
    })(this, depth);
    return flattend;
  };
  
    console.log([[1], [[3], 2]].flat(1))