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0 pointsnmilo2y ago0 comments

Okay, I was being a bit hyperbolic and I'd rather not go back and forth, but I do really hate the newtype pattern. I'm not sure why they don't introduce something like what Go has, like `type UserID = uint32`.

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jcrites2y ago· 1 in thread

Rust has that, it's called a type alias: https://doc.rust-lang.org/reference/items/type-aliases.html

I'm not familiar with that Go feature, but in Rust it's just introducing another name for a type. I've usually seen it used to introduce simpler names for complex types.

duped2y ago

Type aliases and new types are two subtly different features. The new type pattern allows you to provide new impls for the underlying type (it is a new type after all) while the type alias is pure sugar where type T = U allows the string T to be substituted for U in any place where T is imported. If U is a foreign type you cannot provide new trait impls for it.

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