New function isClass

[MillhioreBT]

Pull Request Prelude

• I have followed proper The Forgotten Server code styling.
• I have read and understood the contribution guidelines before making this PR.
• I am aware that this PR may be closed if the above-mentioned criteria are not fulfilled.

Changes Proposed

This new method would help us know if the datatype belongs to a specific class.
Although we can do the raw comparison using the getmetatable function, it seems more intuitive to have this method with the name isClass

Cases in which it can be useful:

• There are some cases in which a method returns a cylinder and this cylinder can be a player, a container or a tile, so if you want to know if it is a tile, you cannot execute the isTile method, because if it is a player or a container this method does not exist, but in the opposite case if you want to know if the cylinder is a player you can use isPlayer, but if the cylinder happens to be a tile there will be an error because isPlayer does not exist

Example

local event = Event()

function event.onMoveItem(player, item, count, fromPosition, toPosition, fromCylinder, toCylinder)
	if isClass(toCylinder, Tile) then
		player:sendTextMessage(MESSAGE_INFO_DESCR, "To Tile.")
	elseif isClass(toCylinder, Player) then
		player:sendTextMessage(MESSAGE_INFO_DESCR, "To Player.")
	elseif isClass(toCylinder, Container) then
		player:sendTextMessage(MESSAGE_INFO_DESCR, "To Container.")
	end

	return RETURNVALUE_NOERROR
end

event:register()

The other option would be to add all the methods corresponding to all the classes:

• isTile, isPlayer, isCreature, isMonster, isItem, isContainer, isTeleport, isNpc
  and their respective get
• getTile, getPlayer, getCreature, getMonster, getItem, getContainer, getTeleport, getNpc

Issues addressed: Nothing!