24 Ranges library [ranges]

24.3 Range access [range.access]

24.3.4 ranges​::​cend [range.access.cend]

The name ranges​::​cend denotes a customization point object.
The expression ranges​::​cend(E) for some subexpression E of type T is expression-equivalent to:
  • ranges​::​end(static_­cast<const T&>(E)) if E is an lvalue.
  • Otherwise, ranges​::​end(static_­cast<const T&&>(E)).
Note
:
Whenever ranges​::​cend(E) is a valid expression, the types S and I of ranges​::​cend(E) and ranges​::​cbegin(E) model sentinel_­for<S, I>.
— end note
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