macro(SP=DocumentTools:-SetProperty, GP=DocumentTools:-GetProperty);
SP("Text",value,"Hello World! ");
ScrollText := proc( msg, direction::identical("Forward","Reverse"),n::posint:=20 )
    local word, count;
    word:=msg;
    count:=0;

    while count<n do
        if direction = "Reverse" then
            word:=cat(word[2..-1],word[1]):
        else
            word:=cat(word[-1],word[1..-2]):
        end if;
        SP("Text",value,word,refresh);
        Threads:-Sleep(0.1);
                   count:=count+1:
    end do:
end proc: