Module `IStdlib__IOption`

val find_value_exn : 'a option -> 'a: Like Option.value_exn but raises Caml.Not_found when called with None.

val value_default_f : f:(unit -> 'a) -> 'a option -> 'a: Like Option.value ~default:(f ()) but f is called only if None.

val if_none_evalopt : f:(unit -> 'a option) -> 'a option -> 'a option: if_none_evalopt ~f x evaluates to f () if x = None, otherwise returns x. Useful for chaining matchers where the first returning non-None determines the result.

val if_none_eval : f:(unit -> 'a) -> 'a option -> 'a: if_none_eval ~f x evaluates to y if x=Some y else to f (). Useful for terminating chains built with if_none_evalopt. This is exactly the same as value_default_f but with a better name.

val exists2 : 'a option -> 'b option -> f:('a -> 'b -> bool) -> bool: Like Option.exists but gets two parameters.

val map_changed : 'a option -> equal:('a -> 'a -> bool) -> f:('a -> 'a) -> 'a option: Like Option.map but maintain physical equality

include sig ... end

module Let_syntax : sig ... end: Provides signatures for OCaml 4.08 binding operators