stl and exceptions

Question

If I use reserve() to reserve enough elements for a vector, will push_back() (or insert()) throw any exceptions?

Is there a reference somewhere that specifies which stl function throw / not throw any exceptions?

Thank you.

Answer 1

If I use reserve() to reserve enough elements for a vector, will push_back() (or insert()) throw any exceptions?

It won't need to perform a reallocation, and so the vector itself won't throw any exceptions. The elements you're inserting might throw exceptions when being copied into the vector, though, so push_back and insert can still throw exceptions.

Is there a reference somewhere that specifies which stl function throw / not throw any exceptions?

Yes, the C++ standard contains that information.

Answer 2

I would say push_back throws when copy construction throws.

Now an exception safe implementation of std::vector will maintain the vector's state as it was before you called push_back or insert so that you can keep using the object.

Also, have a lookt at Lessons Learned from Specifying Exception-Safety for the C++ Standard Library by David Abrahams.