Method parse

crates/spirv-std/macros/src/image.rs:40–381

(input: ParseStream<'_>)

impl Parse for ImageType {
    fn parse(input: ParseStream<'_>) -> syn::Result<Self> {
        let mut sampled_type = None;
        let mut dimensionality = None;
        let mut arrayed = None;
        let mut depth: Option<ImageDepth> = None;
        let mut format = None;
        let mut multisampled = None;
        let mut sampled: Option<Sampled> = None;
        let mut crate_root = None;
        let mut components = None;

        let starting_span = input.span();

        macro_rules! set_unique {
            ($id:ident = $ex:expr) => {{
                if $id.replace($ex).is_some() {
                    return Err(syn::Error::new(
                        input.span(),
                        concat!("Unexpected duplicate parameter for `", stringify!($id), "`"),
                    ));
                }
            }};
        }

        macro_rules! peek_and_eat_value {
            ($typ:ty) => {{
                if input.peek(syn::Token![=]) {
                    input.parse::<syn::Token![=]>()?;
                    Some(input.parse::<$typ>()?)
                } else {
                    None
                }
            }}
        }

        while !input.is_empty() {
            if input.peek(syn::LitInt) {
                let int = input.parse::<syn::LitInt>().unwrap();
                set_unique!(
                    dimensionality = match (int.base10_digits(), int.suffix()) {
                        ("1", "D" | "d") => Dimensionality::OneD,
                        ("2", "D" | "d") => Dimensionality::TwoD,
                        ("3", "D" | "d") => Dimensionality::ThreeD,
                        _ => return Err(syn::Error::new(int.span(), "Unexpected integer")),
                    }
                );
            } else if input.peek(syn::Ident) {
                let ident = input.parse::<Ident>().unwrap();

                if ident == "buffer" {
                    set_unique!(dimensionality = Dimensionality::Buffer);
                } else if ident == "cube" {
                    set_unique!(dimensionality = Dimensionality::Cube);
                } else if ident == "rect" {
                    set_unique!(dimensionality = Dimensionality::Rect);
                } else if ident == "subpass" {
                    set_unique!(dimensionality = Dimensionality::SubpassData);
                } else if ident == "arrayed" {