{"ast_node_type":"function","tokens":[{"end":66,"kind":"keyword","start":0,"text":"fn"}]}
    fn project_field(&self, bx: &mut Bx, field: FieldIdx) -> Self;
    fn layout(&self) -> TyAndLayout<'tcx>;
    fn project_constant_index(&self, bx: &mut Bx, offset: u64) -> Self;