Is Iterator initialization inside for loop considered bad style, and why?

Question

Typically you will find STL code like this:

for (SomeClass::SomeContainer::iterator Iter = m_SomeMemberContainerVar.begin(); Iter != m_SomeMemberContainerVar.end         


        

Answer 1

No, it's a bad idea to get a hold on iter.end() before the loop starts. If your loop changes the container then the end iterator may be invalidated. Also, the end() method is guaranteed to be O(1).

Premature optimization is the root of all evil.

Also, the compiler may be smarter than you think.