1 #include "mystring.h"

     2 #include <ctype.h>

     3 			

     4 mystring mystring::upper() const

     5 {

     6   const unsigned length = rep->length;

     7   char buf[length+1];

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

     9   bool changed = false;

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

    11     if(isupper(*in)) {

    12       *out = tolower(*in);

    13       changed = true;

    14     }

    15     else

    16       *out = *in;

    17   if(!changed)

    18     return *this;

    19   else

    20     return mystring(buf, length);

    21 }