Macro lazy_static 

macro_rules! lazy_static {
    ($(
        $(#[$attr:meta])*
        $vis:vis static ref $N:ident : $T:ty = $e:expr;
    )+) => { ... };
}

Implementation of lazy_static! that supports hot reloading.

The syntax is similar to the lazy_static crate, but the generated code uses the once_cell::sync::Lazy type internally.