diff --git a/init.lua b/init.lua
index 5d031ca..a14cb29 100644
--- a/init.lua
+++ b/init.lua
@@ -1,8 +1,8 @@
 local modpath = core.get_modpath"i3"
-dofile(modpath .. "/src/operators.lua")
+local _loadfile = dofile(modpath .. "/src/operators.lua")
 
 local function lf(path)
-	return loadfile(modpath .. path)
+	return _loadfile(modpath .. path)
 end
 
 i3 = {
diff --git a/src/api.lua b/src/api.lua
index 59c42ed..0fda2fd 100644
--- a/src/api.lua
+++ b/src/api.lua
@@ -88,7 +88,7 @@ function i3.register_craft(def)
 		end
 
 		for symbol in gmatch(concat(def.grid), ".") do
-			c = c + 1
+			c++
 			def.items[c] = def.key[symbol]
 		end
 	else
@@ -110,7 +110,7 @@ function i3.register_craft(def)
 		end
 
 		for name in gmatch(concat(items, ","), "[%s%w_:]+") do
-			c = c + 1
+			c++
 			def.items[c] = clean_name(name)
 		end
 	end
diff --git a/src/caches.lua b/src/caches.lua
index e1e703f..8f1b802 100644
--- a/src/caches.lua
+++ b/src/caches.lua
@@ -104,7 +104,7 @@ local function drop_table(name, drop)
 		end
 
 		if not di.rarity then
-			count_sure = count_sure + 1
+			count_sure++
 		end
 	end
 end
@@ -146,7 +146,7 @@ local function cache_recipes(item)
 		end
 
 		for k, v in pairs(replacements[item]) do
-			k = k + shift
+			k += shift
 
 			if _recipes[k] then
 				_recipes[k].replacements = v
diff --git a/src/operators.lua b/src/operators.lua
index 8ebfcc0..06e9448 100644
--- a/src/operators.lua
+++ b/src/operators.lua
@@ -1,6 +1,5 @@
 local fmt = string.format
-local _loadfile = loadfile
-local var = "[%w%.%[%]_]"
+local var = "[%w%.%[%]\"\'_]"
 
 local operators = {
 	["([%+%-%*%^/&|])="] = function(a, b, c)
@@ -26,6 +25,14 @@ local operators = {
 	[">>"] = function(a, b)
 		return fmt("bit.rshift(%s, %s)", a, b)
 	end,
+
+	["<<="] = function(a, b)
+		return fmt("%s = bit.lshift(%s, %s)", a, a, b)
+	end,
+
+	[">>="] = function(a, b)
+		return fmt("%s = bit.rshift(%s, %s)", a, a, b)
+	end,
 }
 
 local function compile(data)
@@ -61,6 +68,6 @@ local function _load(path, line, data)
 	return l, err
 end
 
-function loadfile(path)
-	return _load(path) or _loadfile(path)
+return function(path)
+	return _load(path) or loadfile(path)
 end
diff --git a/tests/test_operators.lua b/tests/test_operators.lua
index 0c1e3ab..dc7981c 100644
--- a/tests/test_operators.lua
+++ b/tests/test_operators.lua
@@ -1,24 +1,22 @@
 local a, b, c = 0, 0, 0
-
 b+=1
 c++; local foo = "bar";
 print(c-=1)
 print(c++)
 local t = {
 	a = a++,
-	b = b++,
-	c = c++,
+	b = 2,
+	c = c+=2,
 	d = a&3,
+	e = 1,
 }
+t["b"] <<= 4
 print(dump(t))
-
 --c += 1
 c*=2
-
 local i = 16
 i += i<<4
 print(i) -- 272
-
 print(a+=2) -- 2
 print(c++) -- 3
 print(a-=1) -- -1