...
Note that unevaluated expression operands are used when the declaration of an object is required but the definition of the object is not. For instance, in the following example, the function f()
is overloaded, which relies relying on the unevaluated expression operand to select the desired overload, which is then used to determine the result of the sizeof()
expression:
...
[ISO/IEC 14882-2014] | Clause 5, "Expressions" 20.2.5, "Function template Template declval " |
...