24 Ranges library [ranges]

24.3 Range access [range.access]

24.3.3 ranges​::​cbegin [range.access.cbegin]

The name ranges::cbegin denotes a customization point object.
The expression ranges::​cbegin(E) for some subexpression E of type T is expression-equivalent to:
  • ranges::begin(static_­cast<const T&>(E)) if E is an lvalue.
  • Otherwise, ranges::begin(static_­cast<const T&&>(E)).
Whenever ranges::cbegin(E) is a valid expression, its type models Iterator.
end note