Manuel Simon Hirsig
85 lines
3.4 KiB
Lua
85 lines
3.4 KiB
Lua
local tinsert, setfenv, rawget, setmetatable, mask, add, g = tinsert, setfenv, rawget, setmetatable, bit.band, bit.bor, getfenv(0)
|
|
local DECLARED, ACCESSOR, MUTABLE, PUBLIC = 1, 2, 4, 8
|
|
local ACCESSOR_KEY, MUTABLE_KEY, PUBLIC_KEY = 'accessor', 'mutable', 'public'
|
|
local PROPERTY = {[ACCESSOR_KEY]=ACCESSOR, [MUTABLE_KEY]=MUTABLE, [PUBLIC_KEY]=PUBLIC}
|
|
local _data, _metadata, _modifier_properties, _imports, _envs, _interfaces = {}, {}, {}, {}, {}, {}
|
|
local function error(message, ...) g.error(format(message, unpack(arg))..'\n'..debugstack(3, 5, 0), 3) end
|
|
local metadata_mt = {__index=function() return 0 end}
|
|
local env_mt = {
|
|
__metatable = false,
|
|
__index = function(self, key)
|
|
local value, properties = _data[self][key], _metadata[self][key]
|
|
if mask(DECLARED+ACCESSOR, properties) == DECLARED then
|
|
return value
|
|
elseif mask(ACCESSOR, properties) == ACCESSOR then
|
|
return value(key)
|
|
else
|
|
for _, name in _imports[self] do
|
|
local interface = _interfaces[name]
|
|
if interface and mask(PUBLIC, _metadata[interface][key]) ~= 0 then
|
|
return interface[key]
|
|
end
|
|
end
|
|
return g[key] or error('No field "%s".', key)
|
|
end
|
|
end,
|
|
__newindex = function(self, key, value)
|
|
if not rawget(_metadata[self], key) then
|
|
_metadata[self][key] = DECLARED
|
|
elseif mask(MUTABLE, _metadata[self][key]) == 0 then
|
|
error('Field "%s" is immutable.', key)
|
|
end
|
|
_data[self][key] = value
|
|
end,
|
|
}
|
|
local interface_mt = {
|
|
__metatable = false,
|
|
__index = function(self, key)
|
|
local value, properties = _data[self][key], _metadata[self][key]
|
|
if mask(ACCESSOR+PUBLIC, properties) == PUBLIC then
|
|
return value
|
|
elseif mask(PUBLIC, properties) ~= 0 then
|
|
return value(key)
|
|
else
|
|
error('No field "%s".', key)
|
|
end
|
|
end,
|
|
__newindex = function(self, key, value) self[key](value) end,
|
|
}
|
|
local modifier_mt = {
|
|
__metatable = false,
|
|
__index = function(self, key)
|
|
local property = PROPERTY[key]
|
|
if not property then error('Unknown modifier "%s".', key) end
|
|
_modifier_properties[self] = add(property, _modifier_properties[self])
|
|
return self
|
|
end,
|
|
__newindex = function(self, key, value)
|
|
if rawget(_metadata[self], key) then error('Field "%s" already exists.', key) end
|
|
_metadata[self][key] = _modifier_properties[self]
|
|
_data[self][key] = value
|
|
end,
|
|
}
|
|
local importer_mt = {
|
|
__call = function(self, ...)
|
|
for i=1,arg.n do
|
|
tinsert(_imports[self], arg[i])
|
|
end
|
|
end,
|
|
}
|
|
function g.aux_module(name)
|
|
if not _envs[name] then
|
|
local data, metadata, imports, importer, modifier, env, interface, modifier_accessor
|
|
modifier, importer, env, interface = setmetatable({}, modifier_mt), setmetatable({}, importer_mt), setmetatable({}, env_mt), setmetatable({}, interface_mt)
|
|
function modifier_accessor(key) _modifier_properties[modifier] = DECLARED+PROPERTY[key] return modifier end
|
|
data = {g=g, m=env, import=importer, [ACCESSOR_KEY]=modifier_accessor, [MUTABLE_KEY]=modifier_accessor, [PUBLIC_KEY]=modifier_accessor}
|
|
metadata = setmetatable({g=DECLARED, m=DECLARED, import=DECLARED, [ACCESSOR_KEY]=ACCESSOR, [MUTABLE_KEY]=ACCESSOR, [PUBLIC_KEY]=ACCESSOR}, metadata_mt)
|
|
imports = {}
|
|
_envs[name], _interfaces[name] = env, interface
|
|
_data[modifier], _data[env], _data[interface] = data, data, data
|
|
_metadata[modifier], _metadata[env], _metadata[interface] = metadata, metadata, metadata
|
|
_imports[importer], _imports[env] = imports, imports
|
|
end
|
|
setfenv(2, _envs[name])
|
|
return _interfaces[name]
|
|
end |