JavaScript Master · Game 2

Event Loop Express

Read the code, predict the console, then watch the real event loop run it. Every answer is checked against how JavaScript actually behaves.

Call stack●●●

01Warm-up

level-01.js

1console.log('A');
2function greet() {
3  console.log('B');
4}
5greet();
6console.log('C');

1. Run the code on the stackSync code runs line by line until the call stack is empty.
2. Drain every microtaskPromise callbacks, await and queueMicrotask. All of them, even new ones.
3. Take one task, repeatOne timer callback from the task queue, then back to rule 2.

Tap in the order they print

0/3 · drag to reorder

1>...

2>...

3>...

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