From 09e410b21358e1475261499ccf6a75fac2da12d4 Mon Sep 17 00:00:00 2001 From: Jan Tuomi Date: Mon, 5 Jan 2026 21:15:44 +0200 Subject: Refactor and colocate assets --- content/posts/it-doesnt-mean-that/index.md | 40 ++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 content/posts/it-doesnt-mean-that/index.md (limited to 'content/posts/it-doesnt-mean-that/index.md') diff --git a/content/posts/it-doesnt-mean-that/index.md b/content/posts/it-doesnt-mean-that/index.md new file mode 100644 index 0000000..0fb2988 --- /dev/null +++ b/content/posts/it-doesnt-mean-that/index.md @@ -0,0 +1,40 @@ +--- +title: It doesn't mean that +date: 2024-05-16 +--- + +A plain circle with a small dot in the center + +## When I learned my first programming language + +I learned about functions. + +A _function_ is a thing you can call. The function might then _return_ a value. + +## Then I learned about functional programming + +And learned that those words did not mean that at all. Or at least that was not their full, universal meaning. + +Those _functions_ were actually _procedures_. Or _subroutines_. A function should be mathematical and pure. A mapping from a type to another. + +_Returning_ was not optional. All functions return, explicitly or implicitly, since function application must be assigned a value. + +I learned new words too. + +_Functors_ are containers. _Monads_ are powered-up functors with useful computational context. + +## Now that I’m learning about category theory… + +…I’m learning that those words do not mean what I thought they meant, either. + +_Functions_ are apparently morphisms, or arrows, in the category of types. _Functors_ are not containers, they are morphisms between categories. They are also their own category. + +_Monads_ are — I haven’t gotten to monads yet. + +## I read that they have a Monad in philosophy + +And it means _god_. [¹](it-doesnt-mean-that#fn1) + +--- + +1. More or less. -- cgit v1.3