-
-
Save fr33m0nk/f64c035bdd592d23f6dcab47c7f8a079 to your computer and use it in GitHub Desktop.
Basic Typed Concurrency
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package concurrent | |
import ( | |
"sync/atomic" | |
) | |
type Ref[A any] interface { | |
Get() A | |
Set(a A) | |
UpdateAndGet(f func (A) (A)) A | |
GetAndSet(a A) A | |
Underlying() atomic.Value | |
} | |
func NewRef[A any](a A) Ref[A] { | |
// switch v := a.(type) { | |
// case int64: | |
// default: | |
// _ = v | |
ref := internalRef[A]{} | |
ref.Set(a) | |
return ref | |
// } | |
} | |
type internalRef[A any] struct { | |
value atomic.Value | |
} | |
func (ref internalRef[A]) Underlying() atomic.Value { | |
return ref.value | |
} | |
func (ref internalRef[A]) Get() A { | |
returned := ref.value.Load() | |
return returned.(A) | |
} | |
func (ref internalRef[A]) Set(a A) { | |
ref.value.Store(a) | |
} | |
func (ref internalRef[A]) UpdateAndGet(f func (A) (A) ) A { | |
multiply := func (a A) (A, A) { | |
mod := f(a) | |
return mod, mod | |
} | |
return ModifyRef[A, A](ref, multiply) | |
} | |
func (ref internalRef[A]) GetAndSet(a A) A { | |
old := func (old A) (A, A) { | |
return a, old | |
} | |
return ModifyRef[A](ref, old) | |
} | |
func ModifyRef[A any, B any](ref Ref[A], f func(A) (A, B)) B { | |
updated := false | |
var out B | |
for !updated { | |
a := ref.Get() | |
u, b := f(a) | |
underlying := ref.Underlying() | |
updated = underlying.CompareAndSwap(a, u) | |
if (updated){ | |
out = b | |
} | |
} | |
return out | |
} | |
func TryModifyRef[A any, B any](ref Ref[A], f func (A) (A, B)) *B { | |
var out *B | |
a := ref.Get() | |
u, b := f(a) | |
underlying := ref.Underlying() | |
updated := underlying.CompareAndSwap(a, u) | |
if (updated){ | |
out = &b | |
} | |
return out | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment