Need for Synchronously Determining a Promise’s State
In most cases, you should rely on the asynchronous nature of Promises to handle your operations. However, there might be scenarios where you need to synchronously check a Promise’s state. Here are a few common use cases:
- Error Handling: You may want to take different actions based on whether a Promise has been rejected or not. Synchronous checking can help you make immediate decisions.
- Conditional Execution: Depending on a Promise’s state, you might want to execute specific code paths synchronously.
- Debugging and Logging: For debugging purposes, you may need to know the state of a Promise at a particular point in your code.
Table of Content
- .then() or .catch()
- Wrap Promises in a synchronous function:
How to Synchronously determine a JavaScript Promise’s State
Handling asynchronous operations in JavaScript can be challenging. However, Promises has made this task easier by providing a more elegant and better error management solution. Although Promise-based code is primarily designed to work asynchronously, there may be instances where you need to synchronously determine a Promise’s state for various reasons. In this article, we’ll explore how to do just that.
A Promise represents a value that might not be available yet but will be at some point in the future. It has three states:
- Pending: It is the state when the Promise is created and hasn’t been resolved or rejected yet.
- Fulfilled: The Promise has successfully resolved with a value.
- Rejected: The Promise has encountered an error or exception during its execution of code.