Make global names in default mod use good naming convention and move backwards-compatibility definitions to mods/legacy

data/builtin.lua

@@ -340,6 +340,77 @@ minetest.craftitem_eat = function(hp_change)
 	end
 end
 
+--
+-- Default material types
+--
+
+function minetest.digprop_constanttime(time)
+	return {
+		diggability = "constant",
+		constant_time = time,
+	}
+end
+
+function minetest.digprop_stonelike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * 5,
+		crackiness = 1,
+		crumbliness = -0.1,
+		cuttability = -0.2,
+	}
+end
+
+function minetest.digprop_dirtlike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * 1.2,
+		crackiness = 0,
+		crumbliness = 1.2,
+		cuttability = -0.4,
+	}
+end
+
+function minetest.digprop_gravellike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * 2,
+		crackiness = 0.2,
+		crumbliness = 1.5,
+		cuttability = -1.0,
+	}
+end
+
+function minetest.digprop_woodlike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * 1.0,
+		crackiness = 0.75,
+		crumbliness = -1.0,
+		cuttability = 1.5,
+	}
+end
+
+function minetest.digprop_leaveslike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * (-0.5),
+		crackiness = 0,
+		crumbliness = 0,
+		cuttability = 2.0,
+	}
+end
+
+function minetest.digprop_glasslike(toughness)
+	return {
+		diggablity = "normal",
+		weight = toughness * 0.1,
+		crackiness = 2.0,
+		crumbliness = -1.0,
+		cuttability = -1.0,
+	}
+end
+
 --
 -- Creative inventory
 --

data/mods/experimental/init.lua

@@ -11,7 +11,7 @@ minetest.register_node("experimental:luafurnace", {
 	inventory_image = minetest.inventorycube("furnace_front.png"),
 	paramtype = "facedir_simple",
 	metadata_name = "generic",
-	material = digprop_stonelike(3.0),
+	material = minetest.digprop_stonelike(3.0),
 })
 
 minetest.register_on_placenode(function(pos, newnode, placer)

data/mods/legacy/depends.txt

@@ -0,0 +1,2 @@
+default
+