The promises object
The promises object is the last of the major concepts of asynchronous programming model implemented. We will be looking at promise as a design pattern.
Promise is a relatively new concept in JavaScript, but it's been around for a long time and has been implemented in other languages.
Promise is an abstraction that contains two main properties, which make them easier to work with:
- You can attach more than one callback with a single promise
- Values and states (errors) get passed along
- Due to these properties, a promise makes common asynchronous patterns using callback easy
A promise can be defined as:
A promise is an observable token given from one object to another. Promises wrap an operation and notify their observers when the operation ...
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