Get and robustly cache all JS language-level intrinsics at first require time.

See the syntax described in the JS spec for reference.

Create val
var GetIntrinsic = require('get-intrinsic');
var assert = require('assert');

// static methods
assert.equal(GetIntrinsic('%Math.pow%'), Math.pow);
assert.equal(Math.pow(2, 3), 8);
assert.equal(GetIntrinsic('%Math.pow%')(2, 3), 8);
delete Math.pow;
assert.equal(GetIntrinsic('%Math.pow%')(2, 3), 8);

// instance methods
var arr = [1];
assert.equal(GetIntrinsic('%Array.prototype.push%'), Array.prototype.push);
assert.deepEqual(arr, [1]);

arr.push(2);
assert.deepEqual(arr, [1, 2]);

GetIntrinsic('%Array.prototype.push%').call(arr, 3);
assert.deepEqual(arr, [1, 2, 3]);

delete Array.prototype.push;
GetIntrinsic('%Array.prototype.push%').call(arr, 4);
assert.deepEqual(arr, [1, 2, 3, 4]);

// missing features
delete JSON.parse; // to simulate a real intrinsic that is missing in the environment
assert.throws(() => GetIntrinsic('%JSON.parse%'));
assert.equal(undefined, GetIntrinsic('%JSON.parse%', true));

Simply clone the repo, npm install, and run npm test

Please email @ljharb or see https://tidelift.com/security if you have a potential security vulnerability to report.