Files
aux-addon-ClassicAPI/libs/module.lua
T
Manuel Simon Hirsig abcc782daa refactoring
2016-08-27 12:09:08 +02:00

113 lines
4.5 KiB
Lua

if module then return end
local typeof, tostring, setmetatable, setfenv, unpack, next, pcall, _G = type, tostring, setmetatable, setfenv, unpack, next, pcall, getfenv(0)
local PUBLIC, PRIVATE = 1, 2
local FUNCTION, GETTER, SETTER = 1, 2, 3
local function error(msg, ...) return _G.error(format(msg or '', unpack(arg))..'\n'..debugstack(), 0) end
local function import_error() error 'Invalid imports.' end
local function declaration_error() error 'Invalid declaration.' end
local function collision_error(key) error('"%s" already exists.', key) end
local function nop() end
local function const(v) return function() return v end end
local _state = {}
local declarator_mt = {__metatable=false}
do
local ACCESS, TYPE = {public=PUBLIC, private=PRIVATE}, {call=FUNCTION, get=GETTER, set=SETTER}
local function extract(v)
local f, getter, setter
f, getter, setter, v.call, v.get, v.set = v.call, v.get, v.set, nil, nil, nil
if next(v) or f ~= nil and getter ~= nil then error() end
return f, getter, setter
end
local function declare(state, access, name, data)
state.access[name] = state.access[name] and collision_error(name) or access or state.default_access
for type, value in data do
if typeof(value) ~= 'function' and (type == GETTER or declaration_error()) then
value = const(value == nil and tostring(value) or value)
end
state[type][name] = value
end
end
function declarator_mt:__index(key) local state=_state[self]
if ACCESS[key] and not state.declaration_access then
state.declaration_access = ACCESS[key]
elseif not state.declaration_name or declaration_error() then
state.declaration_name = key
end
return self
end
function declarator_mt:__newindex(key, value) local state=_state[self]
-- if module.access[key] then return end
local type
if state.declaration_name then
type = TYPE[key] or declaration_error()
else
type = typeof(value) == 'function' and FUNCTION or GETTER
end
declare(state, state.declaration_access, key, {[type]=value})
state.declaration_access, state.declaration_name = nil, nil
end
function declarator_mt:__call(value) local state=_state[self]
if state.declaration_name then
local success, f, get, set = pcall(extract, value)
if not success then declaration_error() end
declare(state, state.declaration_access, state.declaration_name, {[FUNCTION]=f, [GETTER]=get, [SETTER]=set})
elseif state.declaration_access or declaration_error() then
state.default_access = state.declaration_access
end
state.declaration_access, state.declaration_name = nil, nil
end
end
local env_mt = {__metatable=false}
function env_mt:__index(key) local state=_state[self]
local get = state[GETTER][key]
if get then return get() end
local f = state[FUNCTION][key]
if f then return f else return _G[key] end
end
function env_mt:__newindex(key, value) local state=_state[self]
if state.access[key] then
local f = state[SETTER][key]
if f then f(value) end
else
return state.declarator[key]
end
end
local interface_mt = {__metatable=false}
function interface_mt:__index(key) local state=_state[self]
if state.access[key] == PUBLIC then
local get = state[GETTER][key]
if get then return get() else return state[FUNCTION][key] end
end
end
function interface_mt:__newindex(key, value) local state=_state[self]
if state.access[key] == PUBLIC then (state[SETTER][key] or nop)(value) end
end
function module(...)
local state, declarator, env, interface, access, functions, getters, setters
declarator, env, interface = setmetatable({}, declarator_mt), setmetatable({}, env_mt), setmetatable({}, interface_mt)
access = {error=PRIVATE, nop=PRIVATE, _G=PRIVATE, M=PRIVATE, I=PRIVATE, public=PRIVATE, private=PRIVATE}
functions = {error=error, nop=nop}
getters = {_G=const(_G), M=const(env), I=const(interface), public=function() state.declaration_access = PUBLIC return declarator end, private=function() state.declaration_access = PRIVATE return declarator end}
setters = {}
for i=1,arg.n do
local module = _state[arg[i] or import_error()] or import_error()
local module_functions, module_getters, module_setters = module[FUNCTION], module[GETTER], module[SETTER]
for k, v in module.access do
if v == PUBLIC and (not access[k] or import_error()) then
functions[k], getters[k], setters[k] = module_functions[k], module_getters[k], module_setters[k]
access[k] = PRIVATE
end
end
end
state = {access=access, [FUNCTION]=functions, [GETTER]=getters, [SETTER]=setters, declarator=declarator, default_access=PRIVATE}
_state[declarator], _state[env], _state[interface] = state, state, state
setfenv(2, env)
end