Today I learned about...

1. Closures and how fundamental they are to mastering Javascript.
2. Currying
3. Did a refresh on Programming Paradigms
4. NodeJS Error Types

Detailed descriptions below

Things I'm curious about today:

1. Websockets
2. Memoization in React
3. Why SSR is so important
4. Are Semantic HTML5 tags really important
5. Practicing writing Promises using async/await

Closures:

• Helpful article The Javascipt Scene
• It provided a succint example of why & how they are important.

Mainly that they control what is and isn't in scope and focus on ensuring Object Data Privacy

...

Currying:

• Syntax:

const curried = fn1 => fn2 => fn1 + fn2

• A great way to use function composition in order to build a new function from an old function by just passing arguments
• Use Cases: memoization | 1st Class Functions | Catching multiple Errors for Validation

Programming Paradigms

• Imperative: Follow a 'How to Do' directive; ex: OOP, Parallel Processing
• Delcarative: Follow a 'What to Do' directive; ex: Functional, Database Processing
• Javascript is a combination of both with elements of OOP & Functional being at its core.
• Great Example of Imperative vs Declaritive

NodeJS Error Types

• Node has 4 types of Error contexts ⋅⋅⋅ Synchronous ⋅⋅⋅ Asynchronous ⋅⋅⋅ Event ⋅⋅⋅ Promise
• Errors: A non fatal condition that can be caught and handled typcially with error 1st callback pattern
• Exceptions: A serious error that a sane environment should not ignore or try to handle i.e. Trigger process restart