reading-notes

Functional Programming

What is functional programming?
- Functional programming is a programming paradigm — a style of building the structure and elements of computer programs — that treats computation as the evaluation of mathematical functions and avoids changing-state and mutable data — Wikipedia - Medium.com
What is a pure function and how do we know if something is a pure function?
- It returns the same result if given the same arguments (it is also referred as deterministic)
- It does not cause any observable side effects
What are the benefits of a pure function?
- Pure functions are stable, consistent, and predictable. Given the same parameters, pure functions will always return the same result
- The code’s easier to test
What is immutability?
- When data is immutable, its state cannot change after it’s created
What is Referential transparency?
- if a function consistently yields the same result for the same input, it is referentially transparent.
- pure functions + immutable data = referential transparency

What is a module?
- Basically a JS file
What does the word ‘require’ do?
- returns the exported from whatever is passed to the require func
How do we bring another module into the file the we are working in?
- let someVariable = require('./pathToTheThingINeed')
What do we have to do to make a module available?
- module.exports = theThingsToExportFromThisFile;