#[derive(Debug)]
pub struct Context {
    pub name: String
}


impl Context {
    pub fn new(string: &str) -> Context {
        Context {
            name: String::from(string)
        }
    }
}

#[derive(Debug)]
pub struct Data<'a> {
    pub data: Vec<f32>,
    pub context: &'a mut Context
}

impl<'a> Data<'a> {
    pub fn new(context: &'a mut Context) -> Data<'a> {
        Data {
            data: Vec::new(),
            context
        }
    }

    pub fn from_slice(data: &[f32], context: &'a mut Context) -> Data<'a> {
        Data {
            data: data.to_vec(),
            context
        }
    }

    pub fn clear(&mut self) {
        self.data = Vec::new()
    }
}

fn push_more(d: &mut Data) {
    d.data.push(3.0);
}

fn main() {
    let mut context = Context::new("my context");
    let mut d = Data::from_slice(&[1.0, 2.0, 3.0], &mut context);
    d.clear();
    d.data.push(1.0);
    d.data.push(2.0);
    d.context.name.push_str("!");
    push_more(&mut d);

    println!("{:?}", d);
}