package core

  1. Overview
  2. Docs
package core
Legend:
Library
Module
Module type
Parameter
Class
Class type

Option.t is like t option, except that the value is immediate. This module should mainly be used to avoid allocations.

type value := t
type t = private Span.Option.t
include Ppx_compare_lib.Comparable.S with type t := t
include Bin_prot.Binable.S with type t := t
include Bin_prot.Binable.S_only_functions with type t := t
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (int -> t) Bin_prot.Read.reader

This function only needs implementation if t exposed to be a polymorphic variant. Despite what the type reads, this does *not* produce a function after reading; instead it takes the constructor tag (int) before reading and reads the rest of the variant t afterwards.

val bin_shape_t : Bin_prot.Shape.t
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_reader_t : t Bin_prot.Type_class.reader
include Immediate_option.S_int63 with type value := value with type t := t
include Immediate_option_intf.S_without_immediate with type t := t with type value := value
include Ppx_compare_lib.Comparable.S with type t := t
include Ppx_hash_lib.Hashable.S with type t := t
val hash_fold_t : t Base__Ppx_hash_lib.hash_fold
val hash : t -> Base__Ppx_hash_lib.Std.Hash.hash_value
include Typerep_lib.Typerepable.S with type t := t
val typename_of_t : t Typerep_lib.Typename.t
include Immediate_option_intf.S_without_immediate_plain with type t := t with type value := value

Constructors analogous to None and Some. If not (some_is_representable x) then some x may raise or return none.

val none : t
val some : value -> t
val some_is_representable : value -> Base.Bool.t

For some representations of immediate options, the encodings of none and some overlap. For these representations, some_is_representable value = false if value cannot be represented as an option. For example, Int.Option uses min_value to represent none. For other representations, some_is_representable always returns true.

val is_none : t -> Base.Bool.t
val is_some : t -> Base.Bool.t
val value : t -> default:value -> value

value (some x) ~default = x and value none ~default = default.

val value_exn : t -> value

value_exn (some x) = x. value_exn none raises. Unlike Option.value_exn, there is no ?message argument, so that calls to value_exn that do not raise also do not have to allocate.

val unchecked_value : t -> value

unchecked_value (some x) = x. unchecked_value none returns an unspecified value. unchecked_value t is intended as an optimization of value_exn t when is_some t is known to be true.

val to_option : t -> value Base.Option.t
val of_option : value Base.Option.t -> t
module Optional_syntax : Optional_syntax.S with type t := t with type value := value
include Quickcheck.S with type t := t
val quickcheck_generator : t Base_quickcheck.Generator.t
val quickcheck_observer : t Base_quickcheck.Observer.t
val quickcheck_shrinker : t Base_quickcheck.Shrinker.t
module Stable : sig ... end
val sexp_of_t : [ `Use_Time_ns_unix ]
  • deprecated [since 2023-09] Use [Time_ns_unix.Option]
val (>=) : t -> t -> bool
val (<=) : t -> t -> bool
val (=) : t -> t -> bool
val (>) : t -> t -> bool
val (<) : t -> t -> bool
val (<>) : t -> t -> bool
val equal : t -> t -> bool
val compare : t -> t -> int
val min : t -> t -> t
val max : t -> t -> t
module Alternate_sexp : sig ... end

Just like Time_ns.Alternate_sexp, this is different from the sexp format exposed in Time_ns_unix. See the comment above.

OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct