read-only 0.1.0

Read-only field exposure and safe composition helpers via proc macros
Documentation 
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use core::ops::Deref;
use read_only::embed;

#[embed]
pub struct Labelled {
    #[readonly]
    pub label: String,
    pub mutable: i32,
}

impl Labelled {
    pub fn new(label: &str, mutable: i32) -> Self {
        Self {
            read_only: ReadOnlyLabelled {
                label: label.to_string(),
            },
            mutable,
        }
    }
}

impl Deref for ReadOnlyLabelled {
    type Target = str;

    fn deref(&self) -> &Self::Target {
        &self.label
    }
}

fn main() {
    let item = Labelled::new("arcade", 0);

    // Labelled dereferences to ReadOnlyLabelled, and ReadOnlyLabelled
    // dereferences to str, so consumers can use str methods directly.
    assert_eq!(item.len(), 6);
    assert!(item.starts_with("arc"));
    assert_eq!(item.mutable, 0);
}