The header provides partial specializations of move_only_function for each combination of the possible replacements of the placeholders cv, ref, and noex where

• cv is either const or empty,
• ref is either &, &&, or empty, and
• noex is either true or false.

For each of the possible combinations of the placeholders mentioned above, there is a placeholder inv-quals defined as follows:

• If ref is empty, let inv-quals be cv&,
• otherwise, let inv-quals be cv ref.