Re: [boost] formatter

From: nbecker_at_[hidden]
Date: 2001-12-13 08:42:38

An approach I have used to a limited degree is to convert objects to
be printed into a special print object that encapsulates all the
information necessary to print into the desired format.

For example, I want to print a number in hex with some special
format:

struct HexObj {
  HexObj (int _x, int _bits) : x (_x), bits (_bits) {}
  int x;
  int bits;
};

inline ostream& operator << (ostream& os, const HexObj& h) {
  return PrintHex (os, h.bits, h.x, 0);
}

cout << hexobj (2, <parameters>);

In case you're wondering:

inline ostream& PrintHex (ostream& os, int width, int x, char ret = '\n') {
  const int mask = ~(unsigned(-1) << width);
  os << std::hex << std::setw ((width+3)/4) << std::setfill ('0') << (x & mask);
  if (ret)
    os << ret;
  return os;
}