-------------------------------------------------------------------------------------- TableTools ---- ---- This module includes a number of functions for dealing with Lua tables. ---- It is a meta-module, meant to be called from other Lua modules, and should not ---- be called directly from #invoke. --------------------------------------------------------------------------------------
local libraryUtil = require('libraryUtil')
local p =
-- Define often-used variables and functions.local floor = math.floorlocal infinity = math.hugelocal checkType = libraryUtil.checkTypelocal checkTypeMulti = libraryUtil.checkTypeMulti
-------------------------------------------------------------------------------------- isPositiveInteger---- This function returns true if the given value is a positive integer, and false-- if not. Although it doesn't operate on tables, it is included here as it is-- useful for determining whether a given table key is in the array part or the-- hash part of a table.------------------------------------------------------------------------------------function p.isPositiveInteger(v) return type(v)
v and v < infinityend
-------------------------------------------------------------------------------------- isNan---- This function returns true if the given number is a NaN value, and false if-- not. Although it doesn't operate on tables, it is included here as it is useful-- for determining whether a value can be a valid table key. Lua will generate an-- error if a NaN is used as a table key.------------------------------------------------------------------------------------function p.isNan(v) return type(v)
-------------------------------------------------------------------------------------- shallowClone---- This returns a clone of a table. The value returned is a new table, but all-- subtables and functions are shared. Metamethods are respected, but the returned-- table will have no metatable of its own.------------------------------------------------------------------------------------function p.shallowClone(t) checkType('shallowClone', 1, t, 'table') local ret = for k, v in pairs(t) do ret[k] = v end return retend
-------------------------------------------------------------------------------------- removeDuplicates---- This removes duplicate values from an array. Non-positive-integer keys are-- ignored. The earliest value is kept, and all subsequent duplicate values are-- removed, but otherwise the array order is unchanged.------------------------------------------------------------------------------------function p.removeDuplicates(arr) checkType('removeDuplicates', 1, arr, 'table') local isNan = p.isNan local ret, exists =, for _, v in ipairs(arr) do if isNan(v) then -- NaNs can't be table keys, and they are also unique, so we don't need to check existence. ret[#ret + 1] = v elseif not exists[v] then ret[#ret + 1] = v exists[v] = true end end return retend
-------------------------------------------------------------------------------------- numKeys---- This takes a table and returns an array containing the numbers of any numerical-- keys that have non-nil values, sorted in numerical order.------------------------------------------------------------------------------------function p.numKeys(t) checkType('numKeys', 1, t, 'table') local isPositiveInteger = p.isPositiveInteger local nums = for k in pairs(t) do if isPositiveInteger(k) then nums[#nums + 1] = k end end table.sort(nums) return numsend
-------------------------------------------------------------------------------------- affixNums---- This takes a table and returns an array containing the numbers of keys with the-- specified prefix and suffix. For example, for the table-- and the prefix "a", affixNums will return-- .------------------------------------------------------------------------------------function p.affixNums(t, prefix, suffix) checkType('affixNums', 1, t, 'table') checkType('affixNums', 2, prefix, 'string', true) checkType('affixNums', 3, suffix, 'string', true)
local function cleanPattern(s) -- Cleans a pattern so that the magic characters %.[]*+-?^$ are interpreted literally. return s:gsub('([%(%)%%%.%[%]%*%+%-%?%^%$])', '%%%1') end
prefix = prefix or suffix = suffix or prefix = cleanPattern(prefix) suffix = cleanPattern(suffix) local pattern = '^' .. prefix .. '([1-9]%d*)' .. suffix .. '$'
local nums = for k in pairs(t) do if type(k)
-------------------------------------------------------------------------------------- numData---- Given a table with keys like, returns a table-- of subtables in the format-- .-- Keys that don't end with an integer are stored in a subtable named "other". The-- compress option compresses the table so that it can be iterated over with-- ipairs.------------------------------------------------------------------------------------function p.numData(t, compress) checkType('numData', 1, t, 'table') checkType('numData', 2, compress, 'boolean', true) local ret = for k, v in pairs(t) do local prefix, num = mw.ustring.match(tostring(k), '^([^0-9]*)([1-9][0-9]*)$') if num then num = tonumber(num) local subtable = ret[num] or if prefix
-------------------------------------------------------------------------------------- compressSparseArray---- This takes an array with one or more nil values, and removes the nil values-- while preserving the order, so that the array can be safely traversed with-- ipairs.------------------------------------------------------------------------------------function p.compressSparseArray(t) checkType('compressSparseArray', 1, t, 'table') local ret = local nums = p.numKeys(t) for _, num in ipairs(nums) do ret[#ret + 1] = t[num] end return retend
-------------------------------------------------------------------------------------- sparseIpairs---- This is an iterator for sparse arrays. It can be used like ipairs, but can-- handle nil values.------------------------------------------------------------------------------------function p.sparseIpairs(t) checkType('sparseIpairs', 1, t, 'table') local nums = p.numKeys(t) local i = 0 local lim = #nums return function i = i + 1 if i <= lim then local key = nums[i] return key, t[key] else return nil, nil end endend
-------------------------------------------------------------------------------------- size---- This returns the size of a key/value pair table. It will also work on arrays,-- but for arrays it is more efficient to use the # operator.------------------------------------------------------------------------------------function p.size(t) checkType('size', 1, t, 'table') local i = 0 for _ in pairs(t) do i = i + 1 end return iend
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 elseif type1
'boolean' or type1
local arr = local index = 1 for k in pairs(t) do arr[index] = k index = index + 1 end
if keySort ~= false then keySort = type(keySort)
return arrend
-------------------------------------------------------------------------------------- sortedPairs---- 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) checkType('sortedPairs', 1, t, 'table') checkType('sortedPairs', 2, keySort, 'function', true)
local arr = p.keysToList(t, keySort, true)
local i = 0 return function i = i + 1 local key = arr[i] if key ~= nil then return key, t[key] else return nil, nil end endend
-------------------------------------------------------------------------------------- isArray---- Returns true if the given value is a table and all keys are consecutive-- integers starting at 1.------------------------------------------------------------------------------------function p.isArray(v) if type(v) ~= 'table' then return false end local i = 0 for _ in pairs(v) do i = i + 1 if v[i]
-------------------------------------------------------------------------------------- isArrayLike---- Returns true if the given value is iterable and all keys are consecutive-- integers starting at 1.------------------------------------------------------------------------------------function p.isArrayLike(v) if not pcall(pairs, v) then return false end local i = 0 for _ in pairs(v) do i = i + 1 if v[i]
-------------------------------------------------------------------------------------- invert---- Transposes the keys and values in an array. For example, ->-- . Duplicates are not supported (result values refer to-- the index of the last duplicate) and NaN values are ignored.------------------------------------------------------------------------------------function p.invert(arr) checkType("invert", 1, arr, "table") local isNan = p.isNan local map = for i, v in ipairs(arr) do if not isNan(v) then map[v] = i end end
return mapend
-------------------------------------------------------------------------------------- listToSet---- Creates a set from the array part of the table. Indexing the set by any of the-- values of the array returns true. For example, ->-- . NaN values are ignored as Lua considers them-- never equal to any value (including other NaNs or even themselves).------------------------------------------------------------------------------------function p.listToSet(arr) checkType("listToSet", 1, arr, "table") local isNan = p.isNan local set = for _, v in ipairs(arr) do if not isNan(v) then set[v] = true end end
return setend
-------------------------------------------------------------------------------------- deepCopy---- Recursive deep copy function. Preserves identities of subtables.------------------------------------------------------------------------------------local function _deepCopy(orig, includeMetatable, already_seen) if type(orig) ~= "table" then return orig end -- already_seen stores copies of tables indexed by the original table. local copy = already_seen[orig] if copy ~= nil then return copy end copy = already_seen[orig] = copy -- memoize before any recursion, to avoid infinite loops for orig_key, orig_value in pairs(orig) do copy[_deepCopy(orig_key, includeMetatable, already_seen)] = _deepCopy(orig_value, includeMetatable, already_seen) end if includeMetatable then local mt = getmetatable(orig) if mt ~= nil then setmetatable(copy, _deepCopy(mt, true, already_seen)) end end return copyend
function p.deepCopy(orig, noMetatable, already_seen) checkType("deepCopy", 3, already_seen, "table", true) return _deepCopy(orig, not noMetatable, already_seen or)end
-------------------------------------------------------------------------------------- sparseConcat---- Concatenates all values in the table that are indexed by a number, in order.-- sparseConcat => "acd"-- sparseConcat => "bcd"------------------------------------------------------------------------------------function p.sparseConcat(t, sep, i, j) local arr =
local arr_i = 0 for _, v in p.sparseIpairs(t) do arr_i = arr_i + 1 arr[arr_i] = v end
return table.concat(arr, sep, i, j)end
-------------------------------------------------------------------------------------- length---- Finds the length of an array, or of a quasi-array with keys such as "data1",-- "data2", etc., using an exponential search algorithm. 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 #.-- Note: #frame.args in frame object always be set to 0, regardless of the number-- of unnamed template parameters, so use this function for frame.args.------------------------------------------------------------------------------------function p.length(t, prefix) -- requiring module inline so that which is -- only needed by this one function doesn't get millions of transclusions local expSearch = require("Module:Exponential search") checkType('length', 1, t, 'table') checkType('length', 2, prefix, 'string', true) return expSearch(function (i) local key if prefix then key = prefix .. tostring(i) else key = i end return t[key] ~= nil end) or 0end
-------------------------------------------------------------------------------------- inArray---- Returns true if searchElement is a member of the array, and false otherwise.-- Equivalent to JavaScript array.includes(searchElement) or-- array.includes(searchElement, fromIndex), except fromIndex is 1 indexed------------------------------------------------------------------------------------function p.inArray(array, searchElement, fromIndex) checkType("inArray", 1, array, "table") -- if searchElement is nil, error?
fromIndex = tonumber(fromIndex) if fromIndex then if (fromIndex < 0) then fromIndex = #array + fromIndex + 1 end if fromIndex < 1 then fromIndex = 1 end for _, v in ipairs do if v
searchElement then return true end end end return falseend
-------------------------------------------------------------------------------------- merge---- Given the arrays, returns an array containing the elements of each input array-- in sequence.------------------------------------------------------------------------------------function p.merge(...) local arrays = local ret = for i, arr in ipairs(arrays) do checkType('merge', i, arr, 'table') for _, v in ipairs(arr) do ret[#ret + 1] = v end end return retend
-------------------------------------------------------------------------------------- extend---- Extends the first array in place by appending all elements from the second-- array.------------------------------------------------------------------------------------function p.extend(arr1, arr2) checkType('extend', 1, arr1, 'table') checkType('extend', 2, arr2, 'table')
for _, v in ipairs(arr2) do arr1[#arr1 + 1] = v endend
return p