[#BloombergLP-bdlc-FlatHashSet-contains-0a] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlc.adoc[bdlc]::xref:BloombergLP/bdlc/FlatHashSet.adoc[FlatHashSet]::contains :relfileprefix: ../../../ :mrdocs: Return `true` if this set contains an element having the specified `key`, and `false` otherwise. == Synopsis Declared in `<bdlc_flathashset.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- bool contains(KEY const& key) const; ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#