Module:array

local Array = {} local array_constructor

-- Copy table library so as not to unexpectedly change the behavior of code that -- uses it. local array_methods = mw.clone(table)

-- Create version of table.sort that returns the table. array_methods.sort = function (t, comp) table.sort(t, comp) return t end

-- ipairs and unpack operate on arrays. array_methods.ipairs = ipairs array_methods.unpack = unpack

function array_methods:type local mt = getmetatable(self) return type(mt) == "table" and mt.__type or nil end

function array_methods:adjustIndex(index) index = math.floor(index) if index < 0 then index = #self + index + 1 end return index end

-- string.sub-style slicing. function array_methods:slice(i, j)	if i == nil then i = 1 elseif type(i) == "number" then i = self:adjust_index(i) else error("Expected number, got " .. type(i)) end if j == nil or type(j) == "number" then j = self:adjust_index(j or -1) else error("Expected number, got " .. type(j)) end local new_arr = array_constructor local k = 0 for index = i, j do		k = k + 1 new_arr[k] = self[index] end return new_arr end

-- A function to convert string key-table modules such -- as Module:languages/data/2 into arrays. -- "from" is a bad name. -- field_for_key supplies the field name in which the -- key will be stored. local function to_array(map, field_for_key) m_table = m_table or require "Module:table" local arr = {} local i = 0 for key, val in pairs(map) do		i = i + 1 local new_val = m_table.shallowcopy(val) if field_for_key then new_val[field_for_key] = key end arr[i] = new_val end return array_constructor(arr) end

-- Functions from Module:table that operate on arrays or sparse arrays. -- List copied from Module:table/documentation. local operate_on_array = { -- non-sparse "removeDuplicates", "length", "contains", "serialCommaJoin", "reverseIpairs", "reverse", "invert", "listToSet", "isArray", -- sparse "numKeys", "maxIndex", "compressSparseArray", "sparseIpairs", -- tables in general "shallowcopy", "deepcopy", }

-- Not all of these operate on arrays. local create_new_array = { -- Functions from Module:table that create an array. -- List copied from Module:table/documentation. "removeDuplicates", "numKeys", "compressSparseArray", "keysToList", "reverse", -- Functions from Module:table that create an table. "shallowcopy", "deepcopy", -- Functions from Module:fun that create an array. "map", "filter", }

-- Functions from Module:fun that take an array in the second argument. -- They just have to have the argument order reversed to work as methods of the -- array object. local second_argument_is_array = { "map", "some", "all", "filter" }

-- Add aliases for the functions from Module:table whose names -- contain "array" or "list", which is redundant, and whose names don't conform -- to the usual camel case. -- The key redirects to the value. local alias_of = { compress = "compressSparseArray", keys = "keysToList", toSet = "listToSet", deepCopy = "deepcopy", shallowCopy = "shallowcopy", }

local function get_module_function(key, module, module_name) return module[key] or error("No function named " .. tostring(key) .. " in Module:" .. module_name) end

local function wrap_in_array_constructor(func) return function (...) return array_constructor(func(...)) end end

local function create_array_generating_func(key, module, module_name) return wrap_in_array_constructor(get_module_function(key, module, module_name)) end

local function reverse_arguments(func) return function (a, b)		return func(b, a, true) end end

local function underscore_to_camel_case(str) if type(str) ~= "string" then return str end str = str:gsub("_(.)", string.upper) return str end

local m_table, m_fun local Array = {} Array.__type = "array" function Array:__index(key) if type(key) ~= "string" then return nil end -- Convert underscores to camel case: num_keys -> numKeys. key = underscore_to_camel_case(key) local val = array_methods[key] if val then return val end key = alias_of[key] or key local func m_table = m_table or require "Module:table" if m_table.contains(operate_on_array, key) then if m_table.contains(create_new_array, key) then func = create_array_generating_func(key, m_table, "table") else func = m_table[key] end elseif m_table.contains(second_argument_is_array, key) then m_fun = m_fun or require "Module:fun" local raw_func = reverse_arguments(get_module_function(key, m_fun, "fun")) if m_table.contains(create_new_array, key) then func = wrap_in_array_constructor(raw_func) else func = raw_func end elseif key == "fold" then m_fun = m_fun or require "Module:fun" local raw_func = get_module_function(key, m_fun, "fun") func = function(t, func, accum) return raw_func(func, t, accum) end end if func then array_methods[key] = func return func end end

function Array.__add(a, b)	if type(a) == 'table' and type(b) == 'table' then m_table = m_table or require "Module:table" local new_arr = array_constructor(m_table.shallowcopy(a)) for _, val in ipairs(b) do			new_arr:insert(val) end return new_arr end end

function Array:new(...) local arr if select("#", ...) == 1 and type((...)) == "table" then arr = ... local mt = getmetatable(arr) -- If table has been loaded with mw.loadData, copy it to avoid the -- limitations of it being a virtual table. if mt and mt.mw_loadData then m_table = m_table or require "Module:table" arr = m_table.shallowcopy(arr) end else arr = { ... }	end return setmetatable(arr, self) end

-- Declared as local above. function array_constructor(...) return Array:new(...) end

local array_generating_funcs = { from = to_array } local Array_library_mt = { __call = Array.new, __index = array_generating_funcs } setmetatable(Array, Array_library_mt)

function Array_library_mt:__index(key) key = underscore_to_camel_case(key) key = alias_of[key] or key if array_generating_funcs[key] then return array_generating_funcs[key] end m_table = m_table or require "Module:table" if m_table.contains(create_new_array, key) then local func = create_array_generating_func(key, m_table, "table") array_generating_funcs[key] = func return func end end

return Array