Re: [boost] [contract] move operations and class invariants

Lorenzo Caminiti wrote:

2. How useful is a class like the one above with "crippled" invariants and is_valid() preconditions on all its useful public methods like read()?

A read() member that takes no arguments and returns void is not very realistic. read() can fail, so you can drop its "valid" precondition and just fail when the handle is invalid.