Module:Table

local p = {}

-- A number of functions, most of them imported from wikt:Module:table, a -- spinoff of Module:TableTools.

local libraryUtil = require('libraryUtil') local checkType = libraryUtil.checkType local checkTypeMulti = libraryUtil.checkTypeMulti

local function _check(funcName, expectType) if type(expectType) == "string" then return function(argIndex, arg, nilOk) checkType(funcName, argIndex, arg, expectType, nilOk) end else return function(argIndex, arg, expectType, nilOk) if type(expectType) == "table" then checkTypeMulti(funcName, argIndex, arg, expectType, nilOk) else checkType(funcName, argIndex, arg, expectType, nilOk) end end end end

local function defaultKeySort(item1, item2) -- "number" < "string", so numbers will be sorted before strings. local type1, type2 = type(item1), type(item2) if type1 ~= type2 then return type1 < type2 else -- This will fail with table, boolean, function. return item1 < item2 end end

--[[ Returns a list of the keys in a table, sorted using either a default comparison function or a custom keySort function. ]] function p.keysToList(t, keySort, checked) if not checked then local check = _check('keysToList') check(1, t, 'table') check(2, keySort, { 'function', 'boolean', 'nil' }) end

local list = {} local index = 1 for key, value in pairs(t) do list[index] = key index = index + 1 end

if keySort ~= false then keySort = type(keySort) == 'function' and keySort or defaultKeySort

table.sort(list, keySort) end

return list end

--[[ Iterates through a table, with the keys sorted using the keysToList function. If there are only numerical keys, sparseIpairs is probably more efficient. ]] function p.sortedPairs(t, keySort) local check = _check('keysToList') check(1, t, 'table') check(2, keySort, 'function', true)

local list = p.keysToList(t, keySort, true)

local i = 0 return function() i = i + 1 local key = list[i] if key ~= nil then return key, t[key] else return nil, nil end end end

--[[ Returns true if all keys in the table are consecutive integers starting at 1. --]] function p.isArray(t) checkType("isArray", 1, t, "table")

local i = 0 for k, v in pairs(t) do i = i + 1 if t[i] == nil then return false end end return true end

-- { "a", "b", "c" } -> { a = 1, b = 2, c = 3 } function p.invert(array) checkType("invert", 1, array, "table")

local map = {} for i, v in ipairs(array) do map[v] = i end

return map end

--[[ { "a", "b", "c" } -> { ["a"] = true, ["b"] = true, ["c"] = true } --]] function p.listToSet(t) checkType("listToSet", 1, t, "table")

local set = {} for _, item in ipairs(t) do set[item] = true end

return set end

--[[ Recursive deep copy function. Preserves identities of subtables.

]] local function _deepCopy(orig, includeMetatable, already_seen) -- Stores copies of tables indexed by the original table. already_seen = already_seen or {}

local copy = already_seen[orig] if copy ~= nil then return copy end

if type(orig) == 'table' then copy = {} for orig_key, orig_value in pairs(orig) do copy[deepcopy(orig_key, includeMetatable, already_seen)] = deepcopy(orig_value, includeMetatable, already_seen) end already_seen[orig] = copy

if includeMetatable then local mt = getmetatable(orig) if mt ~= nil then local mt_copy = deepcopy(mt, includeMetatable, already_seen) setmetatable(copy, mt_copy) already_seen[mt] = mt_copy end end else -- number, string, boolean, etc copy = orig end return copy end

function p.deepCopy(orig, noMetatable, already_seen) checkType("deepCopy", 3, already_seen, "table", true)

return _deepCopy(orig, not noMetatable, already_seen) end

--[[ Concatenates all values in the table that are indexed by a number, in order. sparseConcat{ a, nil, c, d } => "acd" sparseConcat{ nil, b, c, d } => "bcd" ]] function p.sparseConcat(t, sep, i, j) local list = {}

local list_i = 0 for _, v in require("Module:TableTools").sparseIpairs(t) do list_i = list_i + 1 list[list_i] = v end

return table.concat(list, sep, i, j) end

--[[ -- This returns the length of a table, or the first integer key n counting from -- 1 such that t[n + 1] is nil. It is similar to the operator #, but may return -- a different value when there are gaps in the array portion of the table. -- Intended to be used on data loaded with mw.loadData. For other tables, use #. --]] function p.length(t) local i = 0 repeat i = i + 1 until t[i] == nil return i - 1 end

function p.inArray(arr, valueToFind) checkType("inArray", 1, arr, "table")

-- if valueToFind is nil, error?

for _, v in ipairs(arr) do if v == valueToFind then return true end end

return false end

return p