25. What are the different error handling patterns that can be used for error handling with promises?
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There are several error handling patterns that can be used for error handling with promises. Here are some common ones:

The Catch-First Pattern:

In this pattern, we first handle any errors using the catch method and then resolve or reject the promise based on whether an error occurred. We can also use the try-catch block to catch errors and handle them in a more structured way.

function fetchData() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      // Simulate network error
      throw new Error("Network error");
    }, 2000);
  });
}

fetchData().then(data => console.log(data))
  .catch(error => {
    console.error("An error occurred:", error);
    // Resolve the promise with an empty value or reject it
    resolve();
  });

The Catch-Last Pattern:

In this pattern, we first handle any resolved values using the then method and then catch any errors using the catch method.

function fetchData() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      // Simulate network error
      throw new Error("Network error");
    }, 2000);
  });
}

fetchData().then(data => console.log(data))
  .catch(error => {
    console.error("An error occurred:", error);
  });

The Combined Pattern:

In this pattern, we use a combination of both the Catch-First and Catch-Last patterns to handle errors and resolved values in a more robust manner.

function fetchData() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      // Simulate network error
      throw new Error("Network error");
    }, 2000);
  });
}

fetchData().then(data => console.log(data))
  .catch(error => {
    console.error("An error occurred:", error);
    // Resolve the promise with an empty value or reject it
    resolve();
  })
  .finally(() => {
    console.log("Promise completed");
  });

In summary, there are several error handling patterns that can be used for error handling with promises. The choice of pattern depends on the specific requirements and use case of the application.

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