The TeX Catalogue OnLine, Entry for verbdef, Ctan Edition

Define commands which expand to verbatim text

The package defines a single command \verbdef (which has a *-form, like \verb). \verbdef will define a robust command whose body expands to verbatim text. By using commands defined by \verbdef, one can put verbatim text into the arguments of commands; since the defined command is robust, it doesn't matter if the argument is moving. (Full details of syntax and caveats about use are in comments in the file itself.)