An ESnext spec-compliant Array.prototype.toSpliced shim/polyfill/replacement that works as far down as ES3.
This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the proposed spec.
Because Array.prototype.toSpliced depends on a receiver (the this value), the main export takes the array to operate on as the first argument.
npm install --save array.prototype.tosplicedvar toSpliced = require('array.prototype.tospliced');
var assert = require('assert');
var input = [5, 4, 3, 2, 1, 0];
var output = toSpliced(input, 2, 2);
assert.notEqual(output, input);
assert.deepEqual(output, [5, 4, 1, 0]);
assert.deepEqual(input, [5, 4, 3, 2, 1, 0]);var toSpliced = require('array.prototype.tospliced');
var assert = require('assert');
/* when Array#toSpliced is not present */
delete Array.prototype.toSpliced;
var shimmed = toSpliced.shim();
assert.equal(shimmed, toSpliced.getPolyfill());
assert.deepEqual(input.toSpliced(), toSpliced(input));var toSpliced = require('array.prototype.tospliced');
var assert = require('assert');
/* when Array#toSpliced is present */
var shimmed = toSpliced.shim();
assert.equal(shimmed, Array.prototype.toSpliced);
assert.deepEqual(input.toSpliced(), toSpliced(input));Simply clone the repo, npm install, and run npm test