No shouldn't check agains get_user_weapon, because player can hold his knife when he respawn.
If you want to check few specific weapons, you can check user_has_weapon().
If you want to check more than few, then use get_user_weapon
s and loop through retrieved list.
You can also use the method i used in there :
http://forums.alliedmods.net/showthread.php?p=553846
But make sure you fully understand the code (and for any method you gonna use).
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