include module type of Core.Option.Let_syntax
val return : 'a -> 'a Base__Option.tval (>>=) : 'a Base__Option.t -> ('a -> 'b Base__Option.t) -> 'b Base__Option.tval (>>|) : 'a Base__Option.t -> ('a -> 'b) -> 'b Base__Option.tval (let+) : 'a option -> ('a -> 'b) -> 'b optionval (and+) : 'a option -> 'b option -> ('a * 'b) optionval (let*) : 'a option -> ('a -> 'b option) -> 'b optionval (and*) : 'a option -> 'b option -> ('a * 'b) option