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I've observed that in the following code:
setTimeout(function(){console.log('setTimeout')}); Promise.resolve(1).then(function(){console.log('promise resolve')}) No matter how many times I execute this, the promise callback always logs before the setTimeout.
My understanding is that both callbacks are scheduled to be executed to the next tick, and I don't really understand what is going on that makes the promise always take precendence over the timeout.
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Timeouts and Promises serve different purposes. setTimeout delays the execution of the code block by a specific time duration. Promises are an interface to allow async execution of code. A promise allows code to continue executing while you wait for another action to complete.
setTimeout(..., 0) is called before Promise.
Promises are the ideal choice for handling asynchronous operations in the simplest manner. They can handle multiple asynchronous operations easily and provide better error handling than callbacks and events.
Yet, that does not guarantee that it's immediately forwarded to the Stack and executed. setTimeout is a guarantee to a minimum time of execution.
Promise.resolve schedules a microtask and the setTimeout schedules a macrotask. And the microtasks are executed before running the next macrotask.
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