use TokenStream;
pub use crate*;
pub use crate*;
pub use crate*;
/// Marks this function to only run, from a single thread at a time.
/// If two threads call the function at the same time,
/// one will be blocked until the other is completed.
///
/// Note they will _also_ be blocked against _all_ functions which are
/// marked with `#[one_at_a_time]`.