/usr/lib/ocaml/batteries/batResult.mli is in libbatteries-ocaml-dev 2.4-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 | (** Monadic results of computations that can raise exceptions *)
(** The type of a result. A result is either [Ok x] carrying the
normal return value [x] or is [Bad e] carrying some indication of an
error. The value associated with a bad result is usually an exception
([exn]) that can be raised.
@since 1.0
*)
type ('a, 'b) t = ('a, 'b) BatPervasives.result = Ok of 'a | Bad of 'b
(** Execute a function and catch any exception as a result. This
function encapsulates code that could throw an exception and returns
that exception as a value.
@since 1.0
*)
val catch: ('a -> 'b) -> 'a -> ('b, exn) t
(** As [catch] but two paramaters. This saves a closure construction
@since 2.0
*)
val catch2: ('a -> 'b -> 'c) -> 'a -> 'b -> ('c, exn) t
(** As [catch] but three paramaters. This saves a closure construction
@since 2.0
*)
val catch3: ('a -> 'b -> 'c -> 'd) -> 'a -> 'b -> 'c -> ('d, exn) t
(** [get (Ok x)] returns [x], and [get (Bad e)] raises [e]. This
function is, in a way, the opposite of the [catch] function
@since 2.0
*)
val get : ('a, exn) t -> 'a
(** [default d r] evaluates to [d] if [r] is [Bad] else [x] when [r] is
[Ok x]
@since 2.0
*)
val default: 'a -> ('a, _) t -> 'a
(** [map_default d f r] evaluates to [d] if [r] is [Bad] else [f x]
when [r] is [Ok x]
@since 2.0
*)
val map_default : 'b -> ('a -> 'b) -> ('a, _) t -> 'b
(** [is_ok (Ok _)] is [true], otherwise [false].
@since 2.0
*)
val is_ok : ('a, 'b) t -> bool
(** [is_bad (Bad _)] is [true], otherwise [false]
@since 2.0
*)
val is_bad : ('a, 'b) t -> bool
(** [is_exn e1 r] is [true] iff [r] is [Bad e2] with [e1=e2] *)
val is_exn : exn -> ('a, exn) t -> bool
(** Convert an [option] to a [result]
@since 1.0 *)
val of_option: 'a option -> ('a, unit) t
(** Convert a [result] to an [option]
@since 1.0 *)
val to_option: ('a, _) t -> 'a option
(** {6 The Result Monad} *)
(** This monad is very similar to the option monad, but instead of
being [None] when an error occurs, the first error in the sequence is
preserved as the return value. *)
module Monad : sig
(** Monadic composition.
[bind r f] proceeds as [f x] if [r] is [Ok x], or returns [r] if
[r] is an error.
@since 2.0
*)
val bind: ('a, 'b) t -> ('a -> ('c, 'b) t) -> ('c, 'b) t
(** as [bind] *)
val ( >>= ): ('a, 'b) t -> ('a -> ('c, 'b) t) -> ('c, 'b) t
(** Monadic return, just encapsulates the given value with Ok *)
val return : 'a -> ('a, _) t
end
(** {6 Infix} *)
(** This infix module provides the operator [(>>=)] *)
module Infix : sig
val ( >>= ): ('a, 'b) t -> ('a -> ('c, 'b) t) -> ('c, 'b) t
end
(** Print a result as Ok(x) or Bad(exn) *)
val print : ('b BatInnerIO.output -> 'a -> unit) -> 'b BatInnerIO.output -> ('a, exn) t -> unit
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