Understanding setImmediate()

The Node.js setImmediate function interacts with the event loop in a special way

When you want to execute some code asynchronously but as soon as possible, one option is to usesetImmediate()Functions provided by Node.js:

setImmediate(() => {
  //run something
})

Any function passed as the setImmediate() parameter is a callback to be executed in the next iteration of the event loop.

howsetImmediate()Different fromsetTimeout(() => {}, 0)(Timeout by 0ms), then fromprocess.nextTick()?

Function passed toprocess.nextTick()After the current operation ends, it will be executed in the current iteration of the event loop. This means it will always be executed beforesetTimeoutwithsetImmediate.

A kindsetTimeout()Callback with a delay of 0ms andsetImmediate(). The order of execution will depend on various factors, but they will all run in the next iteration of the event loop.

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