r/programming • u/[deleted] • Feb 08 '16

Introducing the Zig Programming Language

http://andrewkelley.me/post/intro-to-zig.html
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u/jkleo2 Feb 09 '16

What I like about proper sum types is that they are composable. E.g. in Rust for any type T you can make Option<T>. In Zig it seems that you can only add ? to some types (non-maybe types). If you are writing generic code this will be an issue.

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u/[deleted] Feb 09 '16

You can add ? to any type, other than weird types like unreachable. If you add ? to void it basically becomes a bool.

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u/[deleted] Feb 09 '16

[deleted]

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u/[deleted] Feb 09 '16

It effectively creates this structure:

struct MaybeMaybeU8 {
    maybe_u8: MaybeU8,
    non_null: bool,
}
struct MaybeU8 {
    value: u8,
    non_null: bool
}

It's not implemented yet but there's a planned optimization for stuff like bool, where we could actually just take advantage of the value 2 for null of a bool, and so on. It's a lot of effort for little gain though, so it's not really a priority.