reflect 0.0.1

The "but I thought Rust doesn't have reflection?" memorial brand new way of defining procedural macros.
Documentation
use Ident;
use MakeImpl;
use Module;
use RuntimeType;
use Type;
use WipImpl;

use std::cell::RefCell;
use std::rc::Rc;

#[derive(Clone, Copy)]
pub struct Execution<'a> {
    pub(crate) ty: &'a Type,
    pub(crate) tracker: &'a Tracker,
}

#[derive(Debug, Clone)]
pub(crate) struct Tracker {
    pub(crate) crates: RefCell<Vec<Ident>>,
    pub(crate) impls: RefCell<Vec<Rc<RefCell<WipImpl>>>>,
}

impl<'a> Execution<'a> {
    pub fn load_crate(self, name: &str) -> Module {
        self.tracker.load_crate(name)
    }

    pub fn make_impl<TraitType, SelfType>(
        self,
        trait_type: TraitType,
        self_type: SelfType,
        run: fn(MakeImpl),
    ) where
        TraitType: RuntimeType,
        SelfType: RuntimeType,
    {
        self.tracker
            .make_impl(trait_type.SELF(), self_type.SELF(), run);
    }

    pub fn target_type(self) -> Type {
        self.ty.clone()
    }
}

impl Tracker {
    pub(crate) fn new() -> Self {
        Tracker {
            crates: RefCell::new(Vec::new()),
            impls: RefCell::new(Vec::new()),
        }
    }

    fn load_crate(&self, name: &str) -> Module {
        self.crates.borrow_mut().push(Ident::new(name));
        Module {
            global: false,
            path: vec![name.to_owned()],
        }
    }

    fn make_impl(&self, of: Type, ty: Type, run: fn(MakeImpl)) {
        let wip = Rc::new(RefCell::new(WipImpl {
            of,
            ty,
            functions: Vec::new(),
        }));
        self.impls.borrow_mut().push(wip.clone());
        run(MakeImpl { wip });
    }
}