#include "mystring.h"

#include <ctype.h>

mystring mystring::upper() const

{

  const unsigned length = rep->length;

  char buf[length+1];

  const char* in = rep->buf + length;

  bool changed = false;

  for(char* out = buf+length; out >= buf; in--, out--)

    if(isupper(*in)) {

      *out = tolower(*in);

      changed = true;

    }

    else

      *out = *in;

  if(!changed)

    return *this;

  else

    return mystring(buf, length);

}