Changes
improved module formatting; improved isArray; added isArrayLike; fixed _deepCopy; and improved defaultKeySort, code by User:Alexiscoutinho
------------------------------------------------------------------------------------
-- 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 ---- not be called directly from #invoke. --
------------------------------------------------------------------------------------
local libraryUtil = require('libraryUtil')
local checkTypeMulti = libraryUtil.checkTypeMulti
------------------------------------------------------------------------------------
-- isPositiveInteger
-- hash part of a table.
------------------------------------------------------------------------------------
function p.isPositiveInteger(v)
return type(v) == 'number' and v >= 1 and floor(v) == v and v < infinity
end
------------------------------------------------------------------------------------
-- isNan
--
-- This function returns true if the given number is a NaN value, and falseif-- if not. Although it doesn't operate on tables, it is included here as it isuseful-- useful for determining whether a value can be a valid table key. Lua willgenerate an-- generate an error if a NaN is used as a table key.
------------------------------------------------------------------------------------
function p.isNan(v)
return type(v) == 'number' and tostring(v) == '-nan'
end
------------------------------------------------------------------------------------
-- shallowClone
-- 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
end
------------------------------------------------------------------------------------
-- removeDuplicates
-- removed, but otherwise the array order is unchanged.
------------------------------------------------------------------------------------
function p.removeDuplicates(t)
checkType('removeDuplicates', 1, t, 'table')
local isNan = p.isNan
local ret, exists = {}, {}
for i_, v in ipairs(t) do
if isNan(v) then
-- NaNs can't be table keys, and they are also unique, so we don't need to check existence.
exists[v] = true
end
end
end
return ret
end
------------------------------------------------------------------------------------
-- numKeys
-- 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, v in pairs(t) do
if isPositiveInteger(k) then
nums[#nums + 1] = k
end
------------------------------------------------------------------------------------
-- 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
-- {a1 = 'foo', a3 = 'bar', a6 = 'baz'} and the prefix "a", affixNums willreturn-- return {1, 3, 6}.
------------------------------------------------------------------------------------
function p.affixNums(t, prefix, suffix)
checkType('affixNums', 1, t, 'table')
local nums = {}
for k, v in pairs(t) do if type(k) == 'string' then
local num = mw.ustring.match(k, pattern)
if num then
end
------------------------------------------------------------------------------------
-- numData
--
-- Given a table with keys like ({"foo1", "bar1", "foo2", "baz2")}, returns a table-- of subtables in the format -- { [1] = {foo = 'text', bar = 'text'}, [2] = {foo = 'text', baz = 'text'} }.-- Keys that don't end with an integer are stored in a subtable named "other".The-- 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')
end
------------------------------------------------------------------------------------
-- compressSparseArray
-- ipairs.
------------------------------------------------------------------------------------
function p.compressSparseArray(t)
checkType('compressSparseArray', 1, t, 'table')
end
------------------------------------------------------------------------------------
-- sparseIpairs
-- handle nil values.
------------------------------------------------------------------------------------
function p.sparseIpairs(t)
checkType('sparseIpairs', 1, t, 'table')
end
------------------------------------------------------------------------------------
-- size
-- but for arrays it is more efficient to use the # operator.
------------------------------------------------------------------------------------
function p.size(t)
checkType('size', 1, t, 'table')
local i = 0
for k _ in pairs(t) do
i = i + 1
end
return i
end
local function defaultKeySort(item1, item2)
if type1 ~= type2 then
return type1 < type2
return item1 < item2
end
end
--------------------------------------------------------------------------------------[[keysToList ---- Returns a list an array 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
checkType('keysToList', 1, t, 'table')
checkTypeMulti('keysToList', 2, keySort, { 'function', 'boolean', 'nil' })
end
local index = 1
for key, value k in pairs(t) do listarr[index] = keyk
index = index + 1
end
if keySort ~= false then
keySort = type(keySort) == 'function' and keySort or defaultKeySort
end
end
--[[---------------------------------------------------------------------------------- -- 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 i = 0
return function()
i = i + 1
local key = listarr[i]
if key ~= nil then
return key, t[key]
end
--[[---------------------------------------------------------------------------------- -- isArray---- Returns true if the given value is a table and all keys in the table are consecutive -- integers starting at 1.--]]----------------------------------------------------------------------------------function p.isArray(tv) checkTypeif type("isArray", 1, t, "v) ~= 'table")' then return false end
local i = 0
for k_ in pairs(v) do i = i + 1 if v[i] == nil then return false end end return trueend -------------------------------------------------------------------------------------- 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(tv) do
i = i + 1
if tv[i] == nil then
return false
end
end
-- ------------------------------------------------------------------------------------ invert---- Transposes the keys and values in an array. For example, { "a", "b", "c" } -> -- { a = 1, b = 2, c = 3 }.------------------------------------------------------------------------------------function p.invert(arrayarr) checkType("invert", 1, arrayarr, "table")
local map = {}
for i, v in ipairs(arrayarr) do
map[v] = i
end
return map
end
--[[---------------------------------------------------------------------------------- -- 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, { "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
--[[---------------------------------------------------------------------------------- -- deepCopy---- 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_deepCopy(orig_key, includeMetatable, already_seen)] = deepcopy_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_deepCopy(mt, includeMetatable, already_seen)
setmetatable(copy, mt_copy)
already_seen[mt] = mt_copy
function p.deepCopy(orig, noMetatable, already_seen)
checkType("deepCopy", 3, already_seen, "table", true)
return _deepCopy(orig, not noMetatable, already_seen)
end
--[[---------------------------------------------------------------------------------- -- sparseConcat---- 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 arr = {} local list_i arr_i = 0
for _, v in p.sparseIpairs(t) do
end
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-- the number of unnamed template parameters, so use this function for-- frame.args.--]]----------------------------------------------------------------------------------
function p.length(t, prefix)
-- requiring module inline so that [[Module:Exponential search]]which is -- 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
end) or 0
end
------------------------------------------------------------------------------------
-- inArray
--
-- Returns true if valueToFind is a member of the array, and false otherwise.
------------------------------------------------------------------------------------
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
end
end
return false
end
return p