A comb is classified under the law as household items for
example like umbrella..pencil etc etc..pen knife is other different
story liao lo..
If for example u were cutting an apple suddenly got some idoit
provoke u..u stab him with the fruit knife..U will still be charged
but not so hefty as it original tend to be..Cos u were holding the
knife at tat situation
If the idiot provoke u now then 10mins later u decided to conceal a
knife n stab him..Then u have nothing to say liao be prepared to
sit long long in changi prison liao 
Anyway either way u will kana charged as usual..just tat the 1st
one will be abit lenient tats all...