[#beman-optional-optional-03-or_else-01]
= xref:beman.adoc[beman]::xref:beman/optional.adoc[optional]::xref:beman/optional/optional-03.adoc[optional]::or_else
:relfileprefix: ../../../
:mrdocs:

`or_else` overloads

== Synopses

Declared in `<beman/optional/optional.hpp>`

Returns an optional containing the contained value if it has one, or the result of applying `f` to the optional if it does not.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class F>
constexpr
xref:beman/optional/optional-03.adoc[optional<T>]
xref:beman/optional/optional-03/or_else-05.adoc[or_else](F&& f) const &
requires (std::invocable<F> && std::copy_constructible<T>);
----

[.small]#xref:beman/optional/optional-03/or_else-05.adoc[_» more..._]#

Returns an optional containing the contained value if it has one, or the result of calling `f` if it does not.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class F>
constexpr
xref:beman/optional/optional-03.adoc[optional<T>]
xref:beman/optional/optional-03/or_else-04.adoc[or_else](F&& f) &&
requires (std::invocable<F> && std::move_constructible<T>);
----

[.small]#xref:beman/optional/optional-03/or_else-04.adoc[_» more..._]#

== Return Value

* optional
* optional<T>
* auto

== Template Parameters

[cols="1,4"]
|===
|Name|Description

| *F*
| An invocable type returning an optional.
|===

== Parameters

[cols="1,4"]
|===
|Name|Description

| *f*
| The invocable to call if the optional is disengaged.
|===


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