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The big three and exception safety

Lets see how we can relate "the big three" of C++ (copy constructor, copy assignment operator and destructor) to the levels of expception safety.

1. Constructor (default, copy) should provide basic exception guarantee (no memory leakes)
2. copy assignment operator should provide strong exception guarantee (commit-or-rollback)
3. destructor should provide no-throw guarantee. (should not fail)
4. Containter templates should provide all above + exception neutrality (pass the exception thrown by parameter types).

See some earlier posts on this blog for more info on exception safety levels. Also see http://www.boost.org/more/generic_exception_safety.html

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