Initializing a member array in constructor initializer

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  1. How can I do what I want to do (that is, initialize an array in a constructor (not assigning elements in the body)). Is it even possible?

Yes. It’s using a struct that contains an array. You say you already know about that, but then I don’t understand the question. That way, you do initialize an array in the constructor, without assignments in the body. This is what boost::array does.

Does the C++03 standard say anything special about initializing aggregates (including arrays) in ctor initializers? Or the invalidness of the above code is a corollary of some other rules?

A mem-initializer uses direct initialization. And the rules of clause 8 forbid this kind of thing. I’m not exactly sure about the following case, but some compilers do allow it. 

struct A {
  char foo[6];
  A():foo("hello") { } /* valid? */
};

See this GCC PR for further details.

Do C++0x initializer lists solve the problem?

Yes, they do. However your syntax is invalid, I think. You have to use braces directly to fire off list initialization

struct A {
  int foo[3];
  A():foo{1, 2, 3} { }
  A():foo({1, 2, 3}) { } /* invalid */
};

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