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What is meant by callback in programming?

sobes.tech AI

Answer from AI

A callback in programming is a function that is passed as an argument to another function and is invoked after a certain action or event is completed. It allows organizing asynchronous execution and result handling.

For example, in JavaScript:

function fetchData(callback) {
  setTimeout(() => {
    const data = { id: 1, name: 'Test' };
    callback(data); // call callback after data is received
  }, 1000);
}

fetchData(function(result) {
  console.log('Data received:', result);
});

Here, fetchData takes a callback and calls it after a delay, simulating an asynchronous operation. The callback handles the result when it becomes available.

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