Implement promise from scratch (in an evolutionary way) to grasp its core ideas
About the Book
- Start the journey from the simple callback pattern to promise
Start with a simple variable
- Initialize with an object instead of undefined
donemethod on the object
- Send the callback to the object
- Refactor the code
- Handle the errors
- Modularize the code
- Register callbacks after resolving
Eliminate nesting by chainable object
- Create a chainable object
- Create a thenable object
- Eliminate nesting of thenable object
- Register several callbacks before resolving
rejectas static functions
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