<p>Given a function <code>fn</code>, an array or arguments <code>args</code>, and a timeout <code>t</code> in milliseconds, return a cancel function <code>cancelFn</code>.</p> <p>After a delay of <code>t</code>, <code>fn</code> should be called with <code>args</code> passed as parameters <strong>unless</strong> <code>cancelFn</code> was called first. In that case, <code>fn</code> should never be called.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> fn = (x) => x * 5, args = [2], t = 20, cancelTime = 50 <strong>Output:</strong> [{"time": 20, "returned": 10}] <strong>Explanation:</strong> const cancel = cancellable(fn, [2], 20); // fn(2) called at t=20ms setTimeout(cancel, 50); the cancelTime (50ms) is after the delay time (20ms), so fn(2) should be called at t=20ms. The value returned from fn is 10. </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> fn = (x) => x**2, args = [2], t = 100, cancelTime = 50 <strong>Output:</strong> [] <strong>Explanation:</strong> fn(2) was never called because cancelTime (50ms) is before the delay time (100ms). </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> fn = (x1, x2) => x1 * x2, args = [2,4], t = 30, cancelTime = 100 <strong>Output:</strong> [{"time": 30, "returned": 8}] <strong>Explanation:</strong> fn(2, 4) was called at t=30ms because cancelTime > t. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>fn is a function</code></li> <li><code>args is a valid JSON array</code></li> <li><code>1 <= args.length <= 10</code></li> <li><code><font face="monospace">20 <= t <= 1000</font></code></li> <li><code><font face="monospace">10 <= cancelT <= 1000</font></code></li> </ul>