[iterator.cust.move] (original) (raw)

23 Iterators library [iterators]

23.3 Iterator requirements [iterator.requirements]

23.3.3 Customization points [iterator.cust]

23.3.3.1 ranges​::​iter_­move [iterator.cust.move]

The expression ranges​::​iter_­move(E) for a subexpression E is expression-equivalent to:

• iter_­move(E), ifE has class or enumeration type anditer_­move(E) is a well-formed expression when treated as an unevaluated operand, with overload resolution performed in a context that does not include a declaration of ranges​::​iter_­movebut does include the declaration
  void iter_move();
• Otherwise, if the expression *E is well-formed:
  • if *E is an lvalue, std​::​move(*E);
  • otherwise, *E.
• Otherwise, ranges​::​iter_­move(E) is ill-formed.
  [ Note
  :
  This case can result in substitution failure when ranges​::​iter_­move(E)appears in the immediate context of a template instantiation.
  — end note
  ]

If ranges​::​iter_­move(E) is not equal to *E, the program is ill-formed, no diagnostic required.