[#BloombergLP-bslstl-Optional_Base-08-2constructor-01]
= xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bslstl.adoc[bslstl]::xref:BloombergLP/bslstl/Optional_Base-08.adoc[Optional_Base<t_TYPE, false>]::Optional_Base
:relfileprefix: ../../../
:mrdocs:

Constructors

== Synopses

Declared in `<bslstl_optional.h>`

Create a disengaged `Optional_Base` object.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0d4.adoc[Optional_Base]();
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0d4.adoc[_» more..._]#

Create a disengaged `Optional_Base` object.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0f.adoc[Optional_Base](xref:bsl/nullopt_t.adoc[bsl::nullopt_t]);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0f.adoc[_» more..._]#

These allocator‐extended constructors cannot be called, and are provided only to prevent compilation errors when 'optional' is explicitly instantiated.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-04f.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType]);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-04f.adoc[_» more..._]#

Create an `Optional_Base` object whose contained value is initialized by forwarding from the specified `value`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0de.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_ConstructFromForwardRef.adoc[BloombergLP::bslstl::Optional_ConstructFromForwardRef],
    t_ANY_TYPE&& value);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0de.adoc[_» more..._]#

Create a disengaged `Optional_Base` object if the specified `original` object is disengaged, and an `Optional_Base` object with the value of `original.value()` (of `t_ANY_TYPE`) converted to `t_TYPE` otherwise.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-078.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_CopyConstructFromOtherOptional.adoc[BloombergLP::bslstl::Optional_CopyConstructFromOtherOptional],
    xref:BloombergLP/bslstl/Optional_Base-05.adoc[Optional_Base<t_ANY_TYPE>] const& original);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-078.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-054.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_CopyConstructFromStdOptional.adoc[BloombergLP::bslstl::Optional_CopyConstructFromStdOptional],
    std::optional<t_ANY_TYPE> const& original);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-054.adoc[_» more..._]#

Create a disengaged `Optional_Base` object if the specified `original` object is disengaged, and an `Optional_Base` object with the value of `original.value()` (of `t_ANY_TYPE`) converted to `t_TYPE` otherwise. `original` is left in a valid but unspecified state.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-070.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_MoveConstructFromOtherOptional.adoc[BloombergLP::bslstl::Optional_MoveConstructFromOtherOptional],
    xref:BloombergLP/bslstl/Optional_Base-05.adoc[Optional_Base<t_ANY_TYPE>]&& original);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-070.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-04e.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_MoveConstructFromStdOptional.adoc[BloombergLP::bslstl::Optional_MoveConstructFromStdOptional],
    std::optional<t_ANY_TYPE>&& original);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-04e.adoc[_» more..._]#

Create an `Optional_Base` object whose contained value is initialized from the specified `args`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class... t_ARGS>
constexpr
explicit
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-02d.adoc[Optional_Base](
    std::in_place_t,
    t_ARGS&&... args);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-02d.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0db.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:bsl/nullopt_t.adoc[bsl::nullopt_t]);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0db.adoc[_» more..._]#

Create an `Optional_Base` object, which contains the result of invocation of the specified `invocable` with the specified `arg`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<
    class t_INVOCABLE,
    class t_ARG>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0c.adoc[Optional_Base](
    xref:BloombergLP/bslstl/Optional_InvokeConstructorTag.adoc[Optional_InvokeConstructorTag],
    t_INVOCABLE&& invocable,
    t_ARG&& arg);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0c.adoc[_» more..._]#

Create an `Optional_Base` object whose contained value is initialized from the specified `il` and `args`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<
    class t_INIT_LIST_TYPE,
    class... t_ARGS>
constexpr
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-03c.adoc[Optional_Base](
    std::in_place_t,
    std::initializer_list<t_INIT_LIST_TYPE> il,
    t_ARGS&&... args);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-03c.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0a.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:BloombergLP/bslstl/Optional_ConstructFromForwardRef.adoc[BloombergLP::bslstl::Optional_ConstructFromForwardRef],
    t_ANY_TYPE&&);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-0a.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-026.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:BloombergLP/bslstl/Optional_CopyConstructFromOtherOptional.adoc[BloombergLP::bslstl::Optional_CopyConstructFromOtherOptional],
    xref:BloombergLP/bslstl/Optional_Base-05.adoc[Optional_Base<t_ANY_TYPE>] const&);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-026.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-033.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:BloombergLP/bslstl/Optional_CopyConstructFromStdOptional.adoc[BloombergLP::bslstl::Optional_CopyConstructFromStdOptional],
    std::optional<t_ANY_TYPE> const&);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-033.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-071.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:BloombergLP/bslstl/Optional_MoveConstructFromOtherOptional.adoc[BloombergLP::bslstl::Optional_MoveConstructFromOtherOptional],
    xref:BloombergLP/bslstl/Optional_Base-05.adoc[Optional_Base<t_ANY_TYPE>]&&);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-071.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_ANY_TYPE>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-09.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    xref:BloombergLP/bslstl/Optional_MoveConstructFromStdOptional.adoc[BloombergLP::bslstl::Optional_MoveConstructFromStdOptional],
    std::optional<t_ANY_TYPE>&&);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-09.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class... t_ARGS>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-05b.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    std::in_place_t,
    t_ARGS&&...);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-05b.adoc[_» more..._]#


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<
    class t_INIT_LIST_TYPE,
    class... t_ARGS>
xref:BloombergLP/bslstl/Optional_Base-08/2constructor-02b.adoc[Optional_Base](
    std::allocator_arg_t,
    xref:BloombergLP/bslstl/Optional_Base-08/AllocType.adoc[AllocType],
    std::in_place_t,
    std::initializer_list<t_INIT_LIST_TYPE>,
    t_ARGS&&...);
----

[.small]#xref:BloombergLP/bslstl/Optional_Base-08/2constructor-02b.adoc[_» more..._]#


[.small]#Created with https://www.mrdocs.com[MrDocs]#