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What's Functional Programming All About?

www.lihaoyi.com Essays & writing Essays & articles Computer science Class of 2024-09 Hall of Fame
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Resurfaced independently across 4 calendar years, with breakout response in 2 of them.

submissions
10
submitters
7
observed span
2017–2024
peak thread · 153 comments
341 pts
latest 20+ return · 2024-09-04
161 pts

Submission timeline

2007–2026

One slot for every year since HN launched. Height is that year's peak points; orange marks a 100+ point or 50+ comment breakout. Select a bar to open its strongest thread.

First comments on top threads

HN comment order

Functional programming means, that your program is composed out of functions. A function only depends on its input parameters and the effect of applying a function is the returned function result. By this definition, functions don't have side effects. Why do functions and functional programming matter? - Functions are a very nice abstraction. Looking at the input and output values gives you the complete information about the data flow. This makes functions very easy to reason about. - With the…

_ph_·341-point thread·

Author here. This blog post is actually kind of funny; I had a flash of clarity one afternoon that wouldn't go away so I spent 8 hours in a manic frenzy banging it out in one pass with no editing. Not how most of my writing happens (typically its a tedious slog with multiple passes of editing and refinement) Anyone who likes this article on my blog should check out this presentation on applying this philosophy to build tools https://youtu.be/j6uThGxx-18?si=ZF8yOEkd4wxlq84X…

lihaoyi·161-point thread·

This is the best description of data flows used in functional programming I have ever seen. Really well done.

The first top-level comment from each of the four biggest threads, in HN’s own order. Excerpts are shortened; open a comment for full context.

Breakout years
2

100+ points or 50+ comments

Total points
530

reference only — not used in Hall rules or ranking

Total comments
294

reference only — not used in Hall rules or ranking

Every submission

DateTitle as submittedByPointsComments
2017-01-25What's Functional Programming All About?lihaoyi40
2017-01-25What's Functional Programming All About?lihaoyi101
2017-01-28What's Functional Programming All About?lihaoyi30
2017-02-03What's Functional Programming All About?deepakkarki41
2017-02-24How functional programming saves hours of debugging and ramping up to new codegholap20
2017-03-09What's Functional Programming All About?mooreds20
2017-08-31What's Functional Programming All About?First breakout · Best threadpunnerud341139
2019-08-21What's Functional Programming All About?escot20
2021-01-12What’s Functional Programming All About?escot10
2024-09-04What's functional programming all about? (2017)Hall induction · Latest 20+ point returnIvoah161153