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Time spent with a type system buys you compiler-checked proofs of some properties. The important question is whether the time is worth the benefit. One of many

by rictic 8y ago

Time spent with a type system buys you compiler-checked proofs of some properties. The important question is whether the time is worth the benefit. One of many things that I love about the TypeScript type system is that it gives so much power to the author. It is the most expressive industrial type system I know of, but it also makes it easy for the programmer to say "I can't prove that this is true, just trust me that it is". A nice side benefit is that this is also practice, so you can also gain skill. This is how I justify sometimes spending much more time with the type system than it would otherwise be worth when learning a new language or hacking on a personal project.

lmm 8y ago
> One of many things that I love about the TypeScript type system is that it gives so much power to the author. It is the most expressive industrial type system I know of, but it also makes it easy for the programmer to say "I can't prove that this is true, just trust me that it is". I really wanted to like Typescript, but once you're thinking in HKT it's incredibly frustrating to have to manually translate a function into its flattened expansion (just like it's incredibly frustrating to use a type system without generics once you've used one that has generics). Every serious industrial language allows a programmer to say "I can't prove that this is true, just trust me that it is"; I suspect many people who struggle to start out in Haskell would do well to make a little more use of unsafeCoerce and unsafePerformIO (they would no doubt give themselves runtime errors, but sometimes the easiest way to understand why you had a type error is to run the code and see what the values are at runtime). (I made a small hobby tool with ScalaJS and was amazed how easy it was, so I'll be advocating for that over Typescript).

by rictic 8y ago

lmm 8y ago

> One of many things that I love about the TypeScript type system is that it gives so much power to the author. It is the most expressive industrial type system I know of, but it also makes it easy for the programmer to say "I can't prove that this is true, just trust me that it is". I really wanted to like Typescript, but once you're thinking in HKT it's incredibly frustrating to have to manually translate a function into its flattened expansion (just like it's incredibly frustrating to use a type system without generics once you've used one that has generics). Every serious industrial language allows a programmer to say "I can't prove that this is true, just trust me that it is"; I suspect many people who struggle to start out in Haskell would do well to make a little more use of unsafeCoerce and unsafePerformIO (they would no doubt give themselves runtime errors, but sometimes the easiest way to understand why you had a type error is to run the code and see what the values are at runtime). (I made a small hobby tool with ScalaJS and was amazed how easy it was, so I'll be advocating for that over Typescript).