[#bsl-optional-072-and_then-08d]
= xref:bsl.adoc[bsl]::xref:bsl/optional-072.adoc[optional]::and_then
:relfileprefix: ../../
:mrdocs:

`and_then` overloads

== Synopses

Declared in `<bslstl_optional.h>`

If this object contains a value, invoke the specified `func` with the contained value as an argument and return the result of that invocation; otherwise, return an empty optional. Note that `func` must return a specialization of `bsl::optional`. Also note that the return type of `func` does not have to be this object type. Also note that the optional object returned by `func` is returned as‐is, without copying or moving. Finally note that the default allocator is used for constructing the empty optional when `func` is not invoked.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_FUNC>
constexpr
auto
xref:bsl/optional-072/and_then-06.adoc[and_then](t_FUNC&& func) &;
----

[.small]#xref:bsl/optional-072/and_then-06.adoc[_» more..._]#

Invoke the specified `func` on the contained value and return its optional result as a const lvalue.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_FUNC>
constexpr
auto
xref:bsl/optional-072/and_then-080.adoc[and_then](t_FUNC&& func) const &;
----

[.small]#xref:bsl/optional-072/and_then-080.adoc[_» more..._]#

Invoke the specified `func` on the contained value and return its optional result as an rvalue.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_FUNC>
constexpr
auto
xref:bsl/optional-072/and_then-09.adoc[and_then](t_FUNC&& func) &&;
----

[.small]#xref:bsl/optional-072/and_then-09.adoc[_» more..._]#

Invoke the specified `func` on the contained value and return its optional result as a const rvalue.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class t_FUNC>
constexpr
auto
xref:bsl/optional-072/and_then-04.adoc[and_then](t_FUNC&& func) const &&;
----

[.small]#xref:bsl/optional-072/and_then-04.adoc[_» more..._]#


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