make craft recipe conditional

settings.lua

@@ -10,6 +10,7 @@ spawnstep.maxmobs = 1 -- maxiumum number of mobs to allow in area defined by spa
 spawnstep.overmode = false -- whether to look at node above instead of under
 spawnstep.remove = false -- whether to remove the node after spawning
 spawnstep.removeteller = false -- whether to remove the mob determining node after spawning
+spawnstep.craftable = false -- whether the spawn trap is craftable
 
 spawnstep.tiles = { -- define the tiles for the trap node
 	"default_stone.png^default_mese_crystal.png"

trap.lua

@@ -12,14 +12,16 @@ minetest.register_node("spawnstep:spawntrap",{
 	end
 })
 
-core.register_craft({
-	output="spawnstep:spawntrap",
-	recipe={
-		{"","default:mese",""},
-		{"","default:obsidian",""},
-		{"default:diamondblock","default:obsidian","default:diamondblock"},
-	}
-})
+if spawnstep.craftable == true then
+	core.register_craft({
+		output="spawnstep:spawntrap",
+		recipe={
+			{"","default:mese",""},
+			{"","default:obsidian",""},
+			{"default:diamondblock","default:obsidian","default:diamondblock"},
+		}
+	})
+end
 
 
 local count_nearby_mobs = function(pos,radius)