[#mp_units-utility-unspecified_t] = xref:mp_units.adoc[mp_units]::xref:mp_units/utility.adoc[utility]::unspecified_t :relfileprefix: ../../ :mrdocs: Sentinel type for a specializable variable‐template customization point with no usable default. == Synopsis Declared in `<mp‐units/utility/unspecified.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- struct unspecified_t; ---- == Description A variable template cannot be `= delete`d the way a function can, so a customization point that must be specialized before use defaults to an object of this type, and a specialization replaces it with a real value. #specified reports whether that has happened. [.small]#Created with https://www.mrdocs.com[MrDocs]#