Defined in header
template< class >
inline constexpr bool disable_sized_range = false;
sized_rangeconcept specifies the requirements of a
rangetype that knows its size in constant time with the
disable_sized_rangeexists to allows use of range types that provide a
sizefunction (either as a member or as a non-member) but do not in fact model
sized_range. Users may specialize
disable_sized_rangefor cv-unqualified program-defined types. Such specializations shall be usable in constant expressions and have type const bool.
 Semantic requirements
1) Given an lvalue
tof type std::remove_reference_t<T>,
disable_sized_range cannot be used to opt-out a range whose iterator and sentinel satisfy
disable_sized_sentinel_for must be used instead.
disable_sized_range cannot be specialized for array types or reference types.