Question

There are at least two ways to initialize a class in C++.

(1) Initializer List

struct C
{
  int i;
  C() : i(0) {}
};

(2) Initializer Method

struct D
{
  int i;
  C() { init(); }
  void init() {
    i = 0;
  }
};

I need to re-init objects of my class from time to time. With the second solution, I can simply call obj.init(). With the first solution, I would either have to add an init() function which essentially duplicates the initializer list effect or use obj = C().

Is there a more-or-less consensus on what variant is better here? Is there a disadvantage to using an initializer method (except the possible loss of performance as mentioned in the C++ FAQ).

Answer 1

When creating an array (using vector, or allocating dynamically using new) you will have to explicitly call init on each of its members while using a constructor, it will automatically be called for all elements.

I prefer placing basic initialization into the constructor and more complex logic into an init method. In my opinion a constructor should not perform any complex operations.