Typing Is Hard • Hacker News Board

Re: Typing Is Hard

#41

Post by username90 » Wed, Feb 17, 2021, 5:31 AM UTC

yoneda wrote: post #30

username90 wrote: post #22

Earlier quoted context omitted.

I think that having a compromise between types and untyped is best. So first, have a type all other types can be cast to, call it object and allow it to perform generic operations. Then have a type that can be cast to all other types, call it null. These two gives you a lot of the nice parts of untyped languages while still allowing for tooling like quick refactoring or name completions. When I code in a system lacki…

On the contrary, I find myself more productive in languages that do not have pervasive null because then I don't have to manually reason about which values might be null.

People build huge programs in untyped languages, reasoning about null is trivial in comparison. The cost of not having null is that all initialization and generic code gets much harder to write and work with, the benefit is that once in a blue moon you get a hard to debug null pointer error. I've worked as a software engineer at large companies for years and never had a hard to debug null pointer error, so at least to me they don't exist.

Edit: I feel the main problem with over engineered type systems is the same as for any over engineered library. Instead of just cleanly solving a few key issues they recreate a programming language in their types and even worse they force you to use said programming language if you want to code. The C# style type system has all guarantees I need with very few limitations, if I need more guarantees I'll just write them in code.

Re: Typing Is Hard

#42

Post by username90 » Wed, Feb 17, 2021, 5:32 AM UTC

higerordermap wrote: post #35

username90 wrote: post #22

Earlier quoted context omitted.

I think that having a compromise between types and untyped is best. So first, have a type all other types can be cast to, call it object and allow it to perform generic operations. Then have a type that can be cast to all other types, call it null. These two gives you a lot of the nice parts of untyped languages while still allowing for tooling like quick refactoring or name completions. When I code in a system lacki…

so, interface{}

Can you iterate through methods and fields with interface{}? I find great value in being able to go to untyped style code at will.

Re: Typing Is Hard

#43

Post by daurnimator » Wed, Feb 17, 2021, 5:42 AM UTC

> Zig

> undecidable, since evaluation of recursive functions at compile time is possible, thus requiring the compiler to solve the halting problem.

Zig's comptime is limited to the number of backwards branches you allow, see https://ziglang.org/documentation/master/#setEvalBranchQuota

Re: Typing Is Hard

#44

Post by scubbo » Wed, Feb 17, 2021, 5:43 AM UTC

skrebbel wrote: post #5

I think we need new, better concepts to judge type systems by. Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Soundness was Flow's big claim to fame and it just made day to day programming harder with mostly academic/cos…

> infloop

I had never seen this word before, and while I assume it's probably short for "infinite loop", I initially parsed it as "in-floop", as opposed to "out-floop".

Re: Typing Is Hard

#45

Post by refenestrator » Wed, Feb 17, 2021, 5:50 AM UTC

lmm wrote: post #37

skrebbel wrote: post #5

I think we need new, better concepts to judge type systems by. Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Soundness was Flow's big claim to fame and it just made day to day programming harder with mostly academic/cos…

> Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Only if that crowd has never used a good typed language, IME. I spent two weeks trying to get things done in TypeScript and then two days writing them in Scala.js. It's am…

Consider that you might be the weirdo here. Kotlin is eating scala's lunch by specifically jettisoning the advanced type stuff.

If you can give 80% of the value with 20% of the confusion, that's a win for most devs.

Re: Typing Is Hard

#46

Post by lmm » Wed, Feb 17, 2021, 6:06 AM UTC

refenestrator wrote: post #45

lmm wrote: post #37

Earlier quoted context omitted.

> Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Only if that crowd has never used a good typed language, IME. I spent two weeks trying to get things done in TypeScript and then two days writing them in Scala.js. It's am…

Consider that you might be the weirdo here. Kotlin is eating scala's lunch by specifically jettisoning the advanced type stuff. If you can give 80% of the value with 20% of the confusion, that's a win for most devs.

Kotlin is eating Scala's hype by hyping how much better their ad-hoc informally-specified implementation of half the advanced type stuff is. Having had to actually debug errors from their "suspend functions", "platform types" and goodness knows what else, there's nothing simpler about it.

Re: Typing Is Hard

#47

Post by jbluepolarbear » Wed, Feb 17, 2021, 6:41 AM UTC

skrebbel wrote: post #5

I think we need new, better concepts to judge type systems by. Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Soundness was Flow's big claim to fame and it just made day to day programming harder with mostly academic/cos…

Typescript taught me that I actually don’t care about types and all I care about is the shape of data. In most cases I think of types/interfaces in Typescript as strict data definitions. A function takes in a collection of data; as long as the data matches the shape I expect, don’t care what the data represents.

Re: Typing Is Hard

#48

Post by benjaminjackman » Wed, Feb 17, 2021, 6:49 AM UTC

skrebbel wrote: post #5

I think we need new, better concepts to judge type systems by. Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Soundness was Flow's big claim to fame and it just made day to day programming harder with mostly academic/cos…

FWIW I think the core devs of Typescript would disagree with you on the characterization that they were in any way attempting to show a large crowd "that soundness isn't an important property." I just say that because such had been my view of the language as well (pragmatism & productivity over type-system strictness) until I had a feature request rejected on soundness grounds a few days ago.

Re: Typing Is Hard

#49

Post by wutbrodo » Wed, Feb 17, 2021, 6:54 AM UTC

dwhitney wrote: post #28

skrebbel wrote: post #5

I think we need new, better concepts to judge type systems by. Eg TypeScript has convincingly shown to a large crowd that soundness isn't an important property for many key goals of static typing, such as programmer productivity, refactoring support, preventing stupid mistakes and navigating large codebases. Soundness was Flow's big claim to fame and it just made day to day programming harder with mostly academic/cos…

I need to write a blog entry titled, "Your test suite is basically a sh*tty type system." -- I'm in the "totally anal" camp of type system aficionados :)

The earliest example of a remedy for impostor syndrome was during the second year of my professional life, seeing someone on HN say sithour much pushback that "types are superfluous, because you should be writing good unit tests" with reference to engineering systems written in Python. I still think about it sometimes.

Re: Typing Is Hard

#50

Post by wutbrodo » Wed, Feb 17, 2021, 7:00 AM UTC

panzerklein wrote: post #36

dwhitney wrote: post #27

it drives me absolutely insane that this TypeScript compiles: const num: number = [][0]

It won't with --noUncheckedIndexedAccess on.

That seems like a pretty insane default. Do you happen to know what the thinking is? While I'm fortunate enough to have never needed to spend significant time working in JS and its spawn, I've heard a lot of good things from people I respect about TS and its incremental typing approach, so I'm starting from the baseline assumption that this is a reasonable choice.