New helpers for concurrency: lo.Timeout + lo.Deadline + lo.Race

[samber]

• Timeout: func Timeout(duration time.Duration, callback func(done func())) error
• Deadline: func Deadline(duration time.Time, callback func(done func())) error
• Race: func Race(callbacks ...func(done func()))

Timeout and Deadline should not be used when a context is available.

lo.Timeout(2*time.Second, func(done func()) {
    // very long job

   done()

   // free stuff
})

lo.Deadline(myDate, func(done func()) {
    // very long job

   done()

   // free stuff
})

funcA := func(done func()) {
    // very long job

   done()

   // free stuff
}
funcB := func(done func()) {
    // very long job

   done()

   // free stuff
}
funcC := func(done func()) {
    // very long job

   done()

   // free stuff
}

lo.Race(funcA, funcB, funcC)

I'm not really sure Timeout and Deadline should be added to this library, since context.WithTimeout and context.WithDeadline are highly recommended.

For all helpers, isDone func() bool might be passed to callbacks.

Should we add a timeout/deadline to lo.Race()? More helpers lo.RaceWithTimeout() lo.RaceWithDeadline()?

Should lo.Race() return anything ?

WDYT ?