Hi Hans, the \orelse branch can't be used because \c_symb_found still has the same value. Wolfgang \permanent\protected\def\doifelsesymboldefined#1%   {\begingroup    \edef\currentsymbol{#1}%    \let\symb_fetch\symb_fetch_first    \setfalse\c_symb_found    \the\t_symb_setups    \ifconditional\c_symb_found      \endgroup\expandafter\firstoftwoarguments -  \orelse\ifconditional\c_symb_found -    \symb_fetch_second\currentsymbol -    \endgroup\expandafter\firstoftwoarguments -  \else -    \symb_fetch_second\currentsymbol -    \endgroup\expandafter\secondoftwoarguments +  \else +    \symb_fetch_second\currentsymbol +    \ifconditional\c_symb_found +      \endgroup\doubleexpandafter\firstoftwoarguments +    \else +      \endgroup\doubleexpandafter\secondoftwoarguments +    \fi    \fi}