package core_kernel

  1. Overview
  2. Docs
Legend:
Library
Module
Module type
Parameter
Class
Class type
type t
include S_without_immediate_plain with type t := t
type value

The immediate value carried by the immediate option.

Given the presence of unchecked_value, the value type should not have operations that depend on the value's validity for memory safety. In particular, unchecked_value is not called unsafe_value as it would be if it could return a value that later resulted in a segmentation fault. For pointer-like values, use Ext.Nullable, for example.

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