[#BloombergLP-bdlc-FlatHashMap-contains-09]
= xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlc.adoc[bdlc]::xref:BloombergLP/bdlc/FlatHashMap.adoc[FlatHashMap]::contains
:relfileprefix: ../../../
:mrdocs:

Return whether this map contains an element with `key`.

== Synopses

Declared in `<bdlc_flathashmap.h>`

Return whether this map contains an element with `key`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
bool
xref:BloombergLP/bdlc/FlatHashMap/contains-04b.adoc[contains](KEY const& key) const;
----

[.small]#xref:BloombergLP/bdlc/FlatHashMap/contains-04b.adoc[_» more..._]#

Return whether this map contains an element with `key`.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<class LOOKUP_KEY>
bool
xref:BloombergLP/bdlc/FlatHashMap/contains-04c.adoc[contains](LOOKUP_KEY const& key) const
requires BloombergLP::bslmf::IsTransparentPredicate<HASH, LOOKUP_KEY>::value
        &&  BloombergLP::bslmf::IsTransparentPredicate<EQUAL,LOOKUP_KEY>::value;
----

[.small]#xref:BloombergLP/bdlc/FlatHashMap/contains-04c.adoc[_» more..._]#

== Return Value

`true` if an element with `key` exists, and `false` otherwise

== Parameters

[cols="1,4"]
|===
| Name| Description
| *key*
| key to look up
|===


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