Difference between try-catch syntax for function

I came across this syntax recently for try-catch for function.

struct A
{
  int a;

  A (int i) : a(i)  // normal syntax
  {
    try {}
    catch(...) {}
  }

  A ()   // something different
  try : a(0) {}
  catch(...) {}

  void foo ()  // normal function
  try {}
  catch(...) {}
};

Both syntax are valid. Is there any technical difference between these syntax apart from coding style ? Is one of the syntax superior to other by any aspect ?