Struct

There are 3 different types of struct in rust, all of them are supported by derive(Parse) in a very similar way

Named Struct

This is the standard struct that people think about,

#![allow(unused)]
fn main() {
use nommy::{Parse};
#[derive(Parse)]
pub struct FooBar {
    foo: Tag<"foo">,
    bar: Tag<"bar">,
}
}

This will parse the text "foo", then the text "bar". Order matters. If any single field returns an error when parsing, then the struct returns an error too.

Unnamed/Tuple Struct

Rust also provides unnamed structs that are essentially the same, but have unnamed fields

#![allow(unused)]
fn main() {
use nommy::{Parse};
#[derive(Parse)]
pub struct FooBar (
    Tag<"foo">,
    Tag<"bar">,
);
}

This parses exactly the same as the named variety

Unit Struct

Lastly, rust provides unit structs. While these may seem useless in parsing, they do have uses when you configure how the macro should implement Parse.

#![allow(unused)]
fn main() {
use nommy::{Parse};
#[derive(Parse)]
pub struct Unit;
}

This currently parses nothing, the configuration section lets you expand the functionality.