IOption (infer.IStdlib.IOption)

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 iter2 : 'a option -> 'b option -> f:('a -> 'b -> unit) -> unit

Like Option.iter 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

val continue : default:'a -> 'a option -> ('a -> 'a option) -> 'a option

Like Option.bind but keeps continuing the further evaluation with default input when the first parameter is None.

include sig ... end

module Let_syntax : sig ... end

Provides signatures for OCaml 4.08 binding operators