[#BloombergLP-ball-CategoryManager_RadixTree-find-07] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/ball.adoc[ball]::xref:BloombergLP/ball/CategoryManager_RadixTree.adoc[CategoryManager_RadixTree]::find :relfileprefix: ../../../ :mrdocs: Return an optional containing a reference to the non‐modifiable value associated with the specified `key`, or an empty optional if the key is not found. The returned reference remains valid until the tree is modified. == Synopsis Declared in `<ball_categorymanager_radixtree.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- xref:BloombergLP/ball/CategoryManager_RadixTree/OptValueCRef.adoc[CategoryManager_RadixTree<t_VALUE>::OptValueCRef] find(std::string_view const& key) const; ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#