current character, and becomes the current character again. It is an error
if: the @<scanner> has reached end-of-file; the @<scanner> has never been
stepped; or @<character> was not the previous current character.
current character, and becomes the current character again. It is an error
if: the @<scanner> has reached end-of-file; the @<scanner> has never been
stepped; or @<character> was not the previous current character.