5.2 Do's and Don'ts

• Read The C++ FAQ light of comp.lang.c++. This is by far the most useful document you can read while learning C++.
• Trust your compiler. Let it be your friend. Use the warnings: -Wall -W.
• Read what Tiger Assignment says about the use of stl.
• You SHOULD declare your constructors with one argument explicit unless you know you want them to trigger implicit conversions.
• You MUST initialize the attributes of an object with the constructor's member initialization line whenever it's possible.

  Don't write:

            class Foo
            {
            public:
              Foo (int i);
            private:
              int i_;
            };
            
            Foo::Foo (int i)
            {
              i_ = i;
            }
       

  But instead write:

            class Foo
            {
            public:
              Foo (int i);
            private:
              int i_;
            };
            
            Foo::Foo (int i)
              : i_ (i)
            {
            }
       

• When a constructor fails, it MUST throw an exception instead of leaving the newly created object in a zombie state (see this link).
• A destructor MUST NOT fail, that is, it MUST NOT throw an exception (see this link).
• Your destructor MUST be virtual if there is at least one virtual method in your class (see When should my destructor be virtual?).
• You MUST NOT overload operator,, operator|| and operator&&.
• You SHOULD NOT overload operator&.
• You MUST NOT use friends to circumvent bad design.
• You MUST NOT throw literal constants. You SHOULD NOT throw anything else than a temporary object. In particular, you SHOULD NOT throw objects created with new. See this FAQ.
• You MUST NOT put parenthesis after a throw because some compilers (including some versions of gcc) will reject your code. Here is an example of what should not be done:

            int main ()
            {
              throw (Foo ());
            }
       

• You SHOULD catch by reference.
• Once again, you SHOULD really read The C++ FAQ light of comp.lang.c++. This is by far the most useful document you can read while learning C++.