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Comment by oconnor663 | Hacker News Reader

> Would it be fair to say that Zig is to C, what Rust is to C++?

There's definitely something to that analogy, but I think it also misses a lot of really important details. For example, Zig has generics, which right off the bat makes it hard to say that it's "like C". Also Rust enforces memory safety, which isn't like C or C++.

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I mean, C11 also has generics, but I would really suggest not using it X). See https://en.cppreference.com/w/c/language/generic

Of couse, it's a much less powerful feature, there's nothing like interfaces or stuff, just a way to "overload" based on the type.

Thank you. I had no idea that you could do such a thing in C11 preprocessor

_Generic() is not a preprocessor feature, but a "real" language feature (I was confused too when I saw it first though).

The only preprocessor part in the example is mapping the function-like macro 'cbrt(X)' to the language keyword '_Generic(X)'.

i love that zig doesn't have a special syntax for generics, it just allows anything to be resolved at compile-time -- including types. which gives you generics 'for free'.

I've only cursory of Zig, so bear with me. Does this mean that Zig templates are like C++, that is, duck typing? Or is there a notion of constraining the type arguments?

It's duck typed but it's not based on a funky and limited syntax, but rather types at comptime become normal arguments to functions that you can then inspect using normal Zig code.

I wrote a blog post about comptime if you want to learn more: https://kristoff.it/blog/what-is-zig-comptime/

It's duck typed but let's say your "template" takes an integer and divides by two depending on some boolean (perhaps you need to return a lookup table of sometimes half the bitwidth of an integer type). That function called by your template at compile time to maybe-divide-by-two is in the same language as runtime zig, and you could even conceivably call that very same function as a compiled entity in the runtime context.

You can constrain type arguments with a compile-time `if` check, and generate a compile error on violation.

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