--[[ Copyright (c) 2010-2013 Matthias Richter Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. Except as contained in this notice, the name(s) of the above copyright holders shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ]]-- local function include_helper(to, from, seen) if from == nil then return to elseif type(from) ~= 'table' then return from elseif seen[from] then return seen[from] end seen[from] = to for k,v in pairs(from) do k = include_helper({}, k, seen) -- keys might also be tables if to[k] == nil then to[k] = include_helper({}, v, seen) end end return to end -- deeply copies `other' into `class'. keys in `other' that are already -- defined in `class' are omitted local function include(class, other) return include_helper(class, other, {}) end -- returns a deep copy of `other' local function clone(other) return setmetatable(include({}, other), getmetatable(other)) end local function new(class) -- mixins class = class or {} -- class can be nil local inc = class.__includes or {} if getmetatable(inc) then inc = {inc} end for _, other in ipairs(inc) do if type(other) == "string" then other = _G[other] end include(class, other) end -- class implementation class.__index = class class.init = class.init or class[1] or function() end class.include = class.include or include class.clone = class.clone or clone -- constructor call return setmetatable(class, {__call = function(c, ...) local o = setmetatable({}, c) o:init(...) return o end}) end -- interface for cross class-system compatibility (see https://github.com/bartbes/Class-Commons). if class_commons ~= false and not common then common = {} function common.class(name, prototype, parent) return new{__includes = {prototype, parent}} end function common.instance(class, ...) return class(...) end end -- the module return setmetatable({new = new, include = include, clone = clone}, {__call = function(_,...) return new(...) end})