Use connect_to_raillike for rail

Used value: 2

game_api.txt

@@ -194,6 +194,22 @@ xpanes.register_pane(subname, def)
 	^ Recipe field only
 }
 
+Raillike definitions
+--------------------
+The following nodes use the group `connect_to_raillike` and will only connect to
+raillike nodes within this group and the same group value.
+Use `minetest.raillike_group(<Name>)` to get the group value.
+
+| Node type		| Raillike group name
++-----------------------+----------------------------------
+| default:rail		| "rail"
+
+Example:
+If you want to add a new rail type and want it to connect with default:rail,
+add `connect_to_raillike=minetest.raillike_group("rail")` into the `groups` table
+of your node.
+
+
 Default sounds
 --------------
 Sounds inside the default table can be used within the sounds field of node definitions.

mods/default/nodes.lua

@@ -1541,7 +1541,7 @@ minetest.register_node("default:rail", {
                 -- but how to specify the dimensions for curved and sideways rails?
                 fixed = {-1/2, -1/2, -1/2, 1/2, -1/2+1/16, 1/2},
 	},
-	groups = {bendy=2,dig_immediate=2,attached_node=1},
+	groups = {bendy=2,dig_immediate=2,attached_node=1,connect_to_raillike=minetest.raillike_group("rail")},
 })