[#absl-operator_not_eq-0cd2] = xref:absl.adoc[absl]::operator!= :relfileprefix: ../ :mrdocs: Tests whether an `optional_ref` holds a value. == Synopsis Declared in `<absl/types/optional_ref.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- template<typename T> constexpr bool operator!=( std::nullopt_t a, xref:absl/optional_ref-0c.adoc[optional_ref<T>] b); ---- == Return Value `true` if `b` holds a value. == Parameters [cols="1,4"] |=== | Name| Description | *a* | The `std::nullopt` tag. | *b* | The reference to test. |=== [.small]#Created with https://www.mrdocs.com[MrDocs]#