include S_without_immediate 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
Zero.Ext.Nullable, for example.
type t
Represents value option
without allocating a Some
tag. The interface does not
enforce that t
is immediate because some types, like Int63.t
, are only immediate
on 64-bit platforms. For representations whose type is immediate, use S
below
which adds the [@@immediate]
annotation.
include sig ... end
val compare : t ‑> t ‑> Core_kernel__.Import.int
val hash_fold_t : Base.Hash.state ‑> t ‑> Base.Hash.state
val hash : t ‑> Base.Hash.hash_value
val sexp_of_t : t ‑> Base.Sexp.t
val typerep_of_t : t Typerep_lib.Std.Typerep.t
val typename_of_t : t Typerep_lib.Std.Typename.t
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_is_representable : value ‑> Core_kernel__.Import.bool
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 ‑> Core_kernel__.Import.bool
val is_some : t ‑> Core_kernel__.Import.bool
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.
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 Core_kernel__.Import.option
val of_option : value Core_kernel__.Import.option ‑> t
module Optional_syntax : Core_kernel.Optional_syntax.S with type t := t with type value := value