Module Deferred.Memo

Memoization functions like in Core_kernel.Memo, with re-raising of exceptions thrown asynchronously.

Also see Lazy_deferred, of which Deferred.Memo.unit is a special case.

module Deferred : sig ... end
val general : (module Core_kernel.Hashable.S_plain with type t = 'a) -> ('a -> 'b Deferred.t) -> ('a -> 'b Deferred.t) Core_kernel.Staged.t

general hashable f returns a memoized version of f, where the results are stored in a hash table indexed according to hashable. If f a asynchronously raises, then the error is stored in the hash table and is reraised when a is demanded.

Unlike Core_kernel.Memo.general, this general does not support cache_size_bound due to complexities of asynchrony -- even when one has a deferred return by the memoized function, there still may be asynchronous jobs working to determine it.

Unlike Core_kernel.Memo.general, this general takes a required Hashable module argument, to avoid unintentional use of polymorphic comparison.

val unit : (unit -> 'a Deferred.t) -> (unit -> 'a Deferred.t) Core_kernel.Staged.t