API IsInGroup

Returns true if the player is in a group.
 inGroup = IsInGroup([groupType])
==Arguments==
:;groupType: - If omitted, checks if you're in any type of group.
==Returns==
:;inGroup: - Returns true if the player is in the groupType group if specified, or in any type of group.
==Details==
It is possible for a character to belong to a home group at the same time they are in an instance group (LFR or Flex). To distinguish between a party and a raid, use ().
==Patch changes==