Is begin() == end() for any empty() vector?

c++, language-lawyer, stdvector

Solution

Yes, that's what the standard requires it to be for `empty()` for any container.

§ 23.2.1 Table 96 of the C++11 standard says:

 +----------+---------------+----------------------+
 |Expression|  Return Type  | Operational Semantics|
 |----------|---------------|----------------------|
 |a.empty() |Convertible    |a.begin() == a.end()  |
 |          |to bool        |                      |
 |          |               |                      |
 +-------------------------------------------------+

Problem

I have long assumed that for any empty `std::vector` V, `V.begin() == V.end()`. Yet I see nothing in the C++ specification that states this to always be true. Is it necessarily true or does it just happen to be true on most implementations?

Original source