The package provides macros to collect and process a macro
argument (i.e., something which looks like a macro argument) as
a horizontal box rather than as a real macro argument. The
"arguments" are stored as if they had been saved by \savebox or
by the lrbox environment. Grouping tokens \bgroup and \egroup
may be used, which allows the user to have the beginning and
end of a group in different macro invocations, or to place them
in the begin and end code of an environment. Arguments may
contain verbatim material or other special use of characters.
The macros were designed for use within other macros.
