A promise, alone — interactive event loop example
1console.log('start');2 3Promise.resolve().then(() => {4 console.log('from the promise');5});6 7console.log('end');The script begins. console.log("start") runs synchronously on the stack.
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Call stack
script
Web APIs — browser land
The event loop — is the call stack empty? → drain the microtask queue first → then take one callback.
Microtask queue — priority
Callback queue
Console
01start
Fig. — A promise, alone · step 1 of 6
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