• FooBarrington@lemmy.world
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        1 day ago

        It unquestionably is excellent. Can you name another language in common use with a type system that’s close to the expressiveness of Typescript?

        • expr@programming.dev
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          7 hours ago

          Let’s not get ahead of ourselves. Typescript has a decent type system, but it’s hardly state of the art. It’s impressive how they’ve managed to mostly corral JavaScript into something much more sane, but at the end of the day it still suffers greatly from the limitations of JavaScript. They’ve essentially retrofitted some type theory onto JavaScript to make it possible to express JavaScript nonsense in the type system, but there’s plenty of things that would have been designed differently had they been making something from scratch. Not to mention that the type system is unsound by design, which by itself puts it behind languages designed from the ground up to have sound type systems.

          There’s many, many things missing from the type system, like higher-kinded types, type-driven deriving/codegen, generalized algebraic data types (aka GADTs), type families (and relatedly, associated types), existentially-quantified types, and much more.

      • FooBarrington@lemmy.world
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        2 days ago

        How? It’s easy not to run into the common issues by using TS. What’s so bad about it that we should throw away the existing ecosystem?

        Please give arguments instead of platitudes.

        • bleistift2@sopuli.xyz
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          1 day ago

          You don’t need to use TS to avoid common issues. If you add an empty object to an empty array and expect a meaningful result, the problem sits in front of the keyboard.

          • FooBarrington@lemmy.world
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            1 day ago

            Sure, discipline can prevent some errors. But it’s always possible to run into wrong type assumptions, and I’d say type coercion and null/undefined access make up a fairly large percentage of non-logic errors. You can entirely prevent those using Typescript, which is why it’s so useful.

            Static type analysis is always a good idea if you’re writing more than a couple lines. IMO Python is the worst offender with its kwargs etc. - discoverability and testability is just so bad if you’re following common Python idioms.