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Type checking is a symptom, not a solution

(programmingsimplicity.substack.com)
67 points mpweiher | 1 comments | | HN request time: 0.227s | source
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guerrilla ◴[] No.45141819[source]
This is silly. Types are specifications of programs and data. The only reason that isn't obvious is because most of our type systems are rudimentary. It becomes obvious once you pick up anything with a bit more power (Haskell with extensions or any dependently typed programming languages). A type system is not just another ad-hoc solution, it's fundamental and essential to what we're doing. This is obvious if you know the (pre-computer) history of type theory: Types specify sets of objects intensionally. Types describe what our program should do and are also a very clear form of documentation. On top of that, you can't even get rid of types if you wanted. The best you can do is make them implicit. You have to make a decision about how to interpret data in the end, and that's typing. Even assembly language and machine code has types. Even electronics have types, we just don't think of it that way (but look at the 7400-series ICs if you want explicit examples).

This post is written by someone rather naive of computer science. Their description of a "function" betrays that. The failure to recognize UNIX pipelines as function composition also betrays that and so does the whole "black boxes" paragraph.

replies(4): >>45142293 #>>45142585 #>>45142633 #>>45142905 #
1. o11c ◴[] No.45142585[source]
> Types are specifications of programs and data. The only reason that isn't obvious is because most of our type systems are rudimentary.

One major limitation of almost all type systems: they fail to distinguish logical types from representation.