I have figured out by trial and error that
if Therion cannot determine a unique map output title, it assigns a value of ‘sort
of empty but not quite empty’ to \cavename.
What ever that value is, it looks like a
space character, ie blank but with a height that equals a typical text line
height.
It’s not one space, not two spaces,
not an empty string, and I can see I could end up testing a lot of non printing
characters before I find it.
Maybe the programmer can remember what the
magic value is, or someone with better tex skills (than my almost non-existent
tex skills) can offer some code to identify the contents of a string variable,
ie it’s length or much better a list of ascii codes?
code tex-map
\edef\therioninferedmaptitle{\the\cavename}
%save existing calculated cavename to variable
%could put some code here to output the ascii codes contained in \cavename
\edef\nostring{ } %save ‘empty string’ to variable
\ifx\therioninferedmaptitle\nostring
%test if therioninferedmaptitle matches empty string
\cavename={Caves
of the Flora Area} %if
therioninferedmaptitle is empty do this
\else
%if
it's not empty, do nothing, ie keep the value set by therion
\fi
endcode
;- )
Bruce