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Comment by stephc_int13 | Hacker News Reader

Encapsulating arguments inside .{} seems superfluous and noisy.

I'm sure this can be rationalized in some way, to either simplify parsing or solve some rare ambiguity, but I just don't see it.

I know this is a minor thing and can be considered as nitpicky, and I expect some friction with syntax when learning a new language, but I just can't stand things I see as gratuitous. Same with the forced use of _ = foo(.{}); to avoid compiling errors...

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In Zig, function arguments are not wrapped in `.{}`. `.{}` is the syntax for creating a struct or a tuple. This is used as a pattern for allowing optional arguments (options struct) and variadic functions (tuple).

Explicitly discarding return values is a thing many modern programming languages force you to do.

I know, and I don't see unused return values as an error, it should be a warning at best.

And the compiler should be just a bit smarter to avoid the .{} thing when it is not strictly necessary.

> And the compiler should be just a bit smarter to avoid the .{} thing when it is not strictly necessary.

What's your plan for this? Rebuilding the C varargs mess from first principles?

> Encapsulating arguments inside .{} seems superfluous and noisy.

You don't do this? This is only for varargs or optionals.

.{<stuff>} is just a shorthand for Type{<stuff>} (struct constructor) plus, "hey compiler, you figure out the type". So if anything it's LESS noisy than the alternative, and more forward-compatible if you change a type name for example.

I see it this way, the full signature for defining a variable is:

    var foo: Foo = Foo{};

There's two ways to shorten it:

    var foo = Foo{};
    var foo: Foo = .{};

It can infer the type of the var from the right hand side; or the type of the right side from the type of the var.

So when you see .{} as an argument, it is inferring the type from the function signature. It happens to be empty only because it's using default values (or is a tuple with 0 items).

Edit: fixed the extra dots.

that's not quite right.

1) It's var foo = Foo{...}; (no intervening dot)

2) I think parent commenter is referring to function call use case call_my_func(.{...})

1) Ah yes, just typing from memory. Point still stands.

2) Adressed in the last paragraph.

Point being, these two things aren't different (variable assignment and function calls); IIUC they go through the same analysis pathway, result location semantics.

https://ziglang.org/documentation/master/#Result-Location-Se...

It's a little bit weird, since the types flow in the reverse direction than you would expect.

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