isalnum not declared CODE

[Eljay Love-Jensen]

Hi Nicolai,

Your example (with some tweaking) worked on my platform.

My platform is Cygwin / WinXPpro (NT 5.1sp1a) and GCC 3.3.1 (cygming special).

The tweaking should be immaterial.  Things like putting in function bodies 
for String, changing #include <iostream.h> to #include <iostream>, adding 
in "std::" prefixes in the few spots they're needed, changing where top 
points to in the makefile.

Keep in mind that ctype.h is not part of GCC; it's supplied by your 
distribution (Slackware).

It appears that either your GCC was built for a different version of Slackware,
or... you have a filename collision (perhaps due to case insensitive 
filesystem?)
or... you could try putting #include <cctype> in your main.cc

Generally speaking, it's bad practice to name your project's header files 
the same as the system header files.  Even if they differ in case, such as 
<ctype.h> versus "CType.h".

Try this:
g++ -E -dI -c main.cc

That should show you if you are actually including the Slackware 
/usr/include/ctype.h as you expect.  I suspect you are not getting what you 
think you should be getting.

Sincerely,
--Eljay