Undocumented function in TString

Hi,

In the documentation and in the header file of TString there is a function declaration:
Bool_t Tokenize(TString &tok, Ssiz_t &from, const char *delim = " ") const;
However, I found no definition of it anywhere, nor any document about it. Any one know anything about it? And I remember there are a couple of this kind of mysterious functions in other classes.

This signature does not seem to be implemented. See:
root.cern.ch/root/html/src/TString.cxx.html

actually it is here:
root.cern.ch/root/html/src/TRegexp.cxx.html