WoW:API UnitResistance
Appears to return a value describing the base resistance to physical or magical damage. Does not count additional resistance provided by buffs, etc.
Arguments
"Unit" The unit to be evaluated (appears to only work on "player")
"resistanceIndex" Number defining resistance type.
0 - Armor rating
1 - (unknown type)
2 - (unknown type)
3 - (unknown type)
4 - (unknown type)
5 - (unknown type)
6 - (unknown type)
Example
/script SendChatMessage("My base armor is ".. UnitResistance("player", 0)) end;