One thing I don't like about the current definition of ZLE_CHAR_T is
that, in the non-multibyte code, you don't end up with a ZLE_STRING_T
if you take the address of a ZLE_CHAR_T variable (due to ZLE_CHAR_T
being an "int" and ZLE_STRING_T being an "unsigned char *").  Since
we have a ZLE_INT_T for those variables that need to be able to hold
a ZLEEOF value, I thought it would be cleaner to change ZLE_CHAR_T.

For my first try, I changed ZLE_CHAR_T into an "unsigned char", which
caused a bunch of problems with comparisons against char constants,
such as "Comma", because the strings in the rest of zsh are based on
"char", not "unsigned char".  I then decided to change ZLE_CHAR_T to
be a "char" and to also change ZLE_STRING_T into a "char *".  This
change worked with just a few other tweaks to the code, and all the
tests pass.

However, I won't commit this until I hear some assent that this is a
desired change.  Attached is the patch.

..wayne..