class Mutex
pub class Mutex<T>A value that one task at a time holds.
Mutex.lock gives the value to its body only, as a place — m.lock { &n => n += 1; } —
which ends with the body, so nothing reaches the value outside the lock. A task that finds
the mutex held waits, parked, while the other tasks of its thread run. This holds across
threads, and on one thread wherever a body waits.
Methods
pub static fn new(value: T): Mutex<T>Creates a mutex that holds value.
pub fn lock<R, E :: [Error]>(body: fn(&T) -> R throws E): R throws [E, Cancelled]Runs body while the running task holds the mutex and returns what body returns.
The task waits until no other holds the mutex. The body takes the value's place,
{ &v => … }: it reads and writes the value itself, and the place is the call's — it ends
with the body, and no closure in it holds it. The mutex is released when the body ends,
also by a throw.
Errors
Throws what body throws, and Cancelled when the task is cancelled during the wait.