functional programming

TL;DR¹ A programming paradigm that uses functions as a primary way to declare how it should run given input.

Important characteristics:

• Immutability
  • State can’t be changed, new state has to be calculated.
    • Predictable results.
    • Thread safety.
    • etc..
• Pure functions (no side effects).
• Referential Transparency.
  • A pure function can be replaced by it’s expression.

Footnotes

1. Good explanation https://hemaks.org/posts/the-power-of-immutability-in-functional-programming/ ↩