[Click] changing both data and header

[Jessica Shahper]

Hi all!

I want to change the packet data and place some indication about that change in 
the header data, but click does not allow simultaneous change in the packet data 
and the packet header since it has to be either Packet or WritablePacket , would 
it be a good way if I declare the packets as writable packets first and encode 
the contents and then change them to Packets before embedding the information in 
the header? 

Regards,
Jessica