use Base class pattern; extend off existing classes

lips/Base.lua

@@ -0,0 +1,17 @@
+-- mostly just semantics over knife.base
+-- https://github.com/airstruck/knife/blob/master/knife/base.lua
+return {
+    extend = function(self, subtype)
+        subtype = subtype or {}
+        local meta = { __index = subtype }
+        return setmetatable(subtype, {
+            __index = self,
+            __call = function(self, ...)
+                local obj = setmetatable({}, meta)
+                return obj, obj:init(...)
+            end
+        })
+    end,
+
+    init = function() end,
+}

lips/Dumper.lua

@@ -5,10 +5,11 @@ local insert = table.insert
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
 local util = require(path.."util")
+local Base = require(path.."Base")
 
 local bitrange = util.bitrange
 
-local Dumper = util.Class()
+local Dumper = Base:extend()
 function Dumper:init(writer, fn, options)
     self.writer = writer
     self.fn = fn or '(string)'

lips/Lexer.lua

@@ -7,6 +7,7 @@ local insert = table.insert
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
 local util = require(path.."util")
+local Base = require(path.."Base")
 
 local simple_escapes = {
     ['0']   = 0x00,
@@ -21,7 +22,7 @@ local simple_escapes = {
     ['v']   = 0x0B,
 }
 
-local Lexer = util.Class()
+local Lexer = Base:extend()
 function Lexer:init(asm, fn, options)
     self.asm = asm
     self.fn = fn or '(string)'

lips/Muncher.lua

@@ -3,7 +3,7 @@ local insert = table.insert
 
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
-local util = require(path.."util")
+local Base = require(path.."Base")
 local Token = require(path.."Token")
 
 local arg_types = {
@@ -14,7 +14,7 @@ local arg_types = {
     RELLABELSYM = true,
 }
 
-local Muncher = util.Class()
+local Muncher = Base:extend()
 -- no base init method
 
 function Muncher:error(msg)
@@ -26,9 +26,11 @@ function Muncher:token(t, val)
     if type(t) == 'table' then
         t.fn = self.fn
         t.line = self.line
-        return Token(t)
+        local token = Token(t)
+        return token
     else
-        return Token(self.fn, self.line, t, val)
+        local token = Token(self.fn, self.line, t, val)
+        return token
     end
 end
 

lips/Parser.lua

@@ -2,7 +2,6 @@ local insert = table.insert
 
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
-local util = require(path.."util")
 local overrides = require(path.."overrides")
 local Token = require(path.."Token")
 local Lexer = require(path.."Lexer")
@@ -10,7 +9,7 @@ local Dumper = require(path.."Dumper")
 local Muncher = require(path.."Muncher")
 local Preproc = require(path.."Preproc")
 
-local Parser = util.Class(Muncher)
+local Parser = Muncher:extend()
 function Parser:init(writer, fn, options)
     self.fn = fn or '(string)'
     self.main_fn = self.fn

lips/Preproc.lua

@@ -2,7 +2,6 @@ local insert = table.insert
 
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
-local util = require(path.."util")
 local Muncher = require(path.."Muncher")
 local Token = require(path.."Token")
 
@@ -27,7 +26,7 @@ local function RelativeLabel(index, name)
     }
 end
 
-local Preproc = util.Class(Muncher)
+local Preproc = Muncher:extend()
 function Preproc:init(options)
     self.options = options or {}
 end

lips/Token.lua

@@ -1,7 +1,7 @@
 local path = string.gsub(..., "[^.]+$", "")
-local util = require(path.."util")
+local Base = require(path.."Base")
 
-local Token = util.Class()
+local Token = Base:extend()
 function Token:init(...)
     local args = {...}
     if #args == 1 then

lips/overrides.lua

@@ -2,7 +2,6 @@ local insert = table.insert
 
 local path = string.gsub(..., "[^.]+$", "")
 local data = require(path.."data")
-local util = require(path.."util")
 
 local instructions = data.instructions
 

lips/util.lua

@@ -1,21 +1,6 @@
 local floor = math.floor
 local open = io.open
 
-local function Class(inherit)
-    local class = {}
-    local mt_obj = {__index = class}
-    local mt_class = {
-        __call = function(self, ...)
-            local obj = setmetatable({}, mt_obj)
-            obj:init(...)
-            return obj
-        end,
-        __index = inherit,
-    }
-
-    return setmetatable(class, mt_class)
-end
-
 local function readfile(fn, binary)
     local mode = binary and 'rb' or 'r'
     local f = open(fn, mode)
@@ -33,7 +18,6 @@ local function bitrange(x, lower, upper)
 end
 
 return {
-    Class = Class,
     readfile = readfile,
     bitrange = bitrange,
 }