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tialaramex • last Monday at 8:26 AM • 1 reply • view on HN

Surely Rust can infer the type in your example? It just doesn't provide Zig's syntax to use the inferred type to manually initialize. If you wrote some_fn() here where some_fn's return type was genericised, Rust would ask for the appropriately typed some_fn not say it doesn't know the type.

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flohofwoe • last Monday at 9:17 AM

> Surely Rust can infer the type in your example?

Well in Rust code like this:

    pass_action.colors[0] = sg::ColorAttachmentAction {
        load_action: sg::LoadAction::Clear,
        clear_value: sg::Color { r: 0.25, g: 0.5, b: 0.75, a: 1.0 },
        ..Default::default()
    };
...I cannot write:

    pass_action.colors[0] = {
        load_action: sg::LoadAction::Clear,
        clear_value: { r: 0.25, g: 0.5, b: 0.75, a: 1.0 },
        ..Default::default()
    };
...even though the Rust compiler has all the type information it needs (from the 'left-hand-side').

For comparison, in Zig it would look like this:

    pass_action.colors[0] = .{
        .load_action = .Clear,
        .clear_value = .{ .r=0.25, .g=0.5, .b=0.75, .a=1.0 },
    };
...Zig is still only halfway there compared to C99 (e.g. Zig doesn't allow designator chaining and is much less flexible for initializing nested arrays - in those areas it's closer to Rust than C).
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