What are some C++ related idioms, misconceptions, and gotchas that you've learnt from experience?

Question

What are some C++ related idioms, misconceptions, and gotchas that you\'ve learnt from experience?

An example:

class A
{
  public: 
  char s[1024];
  cha         


        

Answer 1

Use boost::spirit::hold_any (link) instead of boost::any for performance code (while holding a large number of small objects). I saw a large difference in their performances.