Module:TableTools: Difference between revisions
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------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- | -- TableTools -- | ||
-- -- | -- -- | ||
-- This module includes a number of functions for dealing with Lua tables. -- | -- 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 | -- 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 libraryUtil = require('libraryUtil') | ||
Line 19: | Line 17: | ||
local checkTypeMulti = libraryUtil.checkTypeMulti | local checkTypeMulti = libraryUtil.checkTypeMulti | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- isPositiveInteger | -- isPositiveInteger | ||
Line 28: | Line 25: | ||
-- hash part of a table. | -- hash part of a table. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.isPositiveInteger(v) | function p.isPositiveInteger(v) | ||
return type(v) == 'number' and v >= 1 and floor(v) == v and v < infinity | |||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- isNan | -- isNan | ||
-- | -- | ||
-- This function returns true if the given number is a NaN value, and false | -- 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) | function p.isNan(v) | ||
return type(v) == 'number' and v ~= v | |||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- shallowClone | -- shallowClone | ||
Line 63: | Line 48: | ||
-- table will have no metatable of its own. | -- table will have no metatable of its own. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.shallowClone(t) | function p.shallowClone(t) | ||
checkType('shallowClone', 1, t, 'table') | |||
local ret = {} | local ret = {} | ||
for k, v in pairs(t) do | for k, v in pairs(t) do | ||
Line 72: | Line 57: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- removeDuplicates | -- removeDuplicates | ||
Line 80: | Line 64: | ||
-- removed, but otherwise the array order is unchanged. | -- removed, but otherwise the array order is unchanged. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.removeDuplicates(arr) | |||
function p.removeDuplicates( | checkType('removeDuplicates', 1, arr, 'table') | ||
checkType('removeDuplicates', 1, | |||
local isNan = p.isNan | local isNan = p.isNan | ||
local ret, exists = {}, {} | local ret, exists = {}, {} | ||
for | for _, v in ipairs(arr) do | ||
if isNan(v) then | if isNan(v) then | ||
-- NaNs can't be table keys, and they are also unique, so we don't need to check existence. | -- NaNs can't be table keys, and they are also unique, so we don't need to check existence. | ||
ret[#ret + 1] = v | ret[#ret + 1] = v | ||
elseif not exists[v] then | |||
ret[#ret + 1] = v | |||
exists[v] = true | |||
end | |||
end | |||
end | end | ||
return ret | return ret | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- numKeys | -- numKeys | ||
Line 106: | Line 86: | ||
-- keys that have non-nil values, sorted in numerical order. | -- keys that have non-nil values, sorted in numerical order. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.numKeys(t) | function p.numKeys(t) | ||
checkType('numKeys', 1, t, 'table') | checkType('numKeys', 1, t, 'table') | ||
local isPositiveInteger = p.isPositiveInteger | local isPositiveInteger = p.isPositiveInteger | ||
local nums = {} | local nums = {} | ||
for k | for k in pairs(t) do | ||
if isPositiveInteger(k) then | if isPositiveInteger(k) then | ||
nums[#nums + 1] = k | nums[#nums + 1] = k | ||
Line 120: | Line 99: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- affixNums | -- affixNums | ||
Line 126: | Line 104: | ||
-- This takes a table and returns an array containing the numbers of keys with the | -- This takes a table and returns an array containing the numbers of keys with the | ||
-- specified prefix and suffix. For example, for the table | -- specified prefix and suffix. For example, for the table | ||
-- {a1 = 'foo', a3 = 'bar', a6 = 'baz'} and the prefix "a", affixNums will | -- {a1 = 'foo', a3 = 'bar', a6 = 'baz'} and the prefix "a", affixNums will return | ||
-- | -- {1, 3, 6}. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.affixNums(t, prefix, suffix) | function p.affixNums(t, prefix, suffix) | ||
checkType('affixNums', 1, t, 'table') | checkType('affixNums', 1, t, 'table') | ||
Line 137: | Line 114: | ||
local function cleanPattern(s) | local function cleanPattern(s) | ||
-- Cleans a pattern so that the magic characters ()%.[]*+-?^$ are interpreted literally. | -- Cleans a pattern so that the magic characters ()%.[]*+-?^$ are interpreted literally. | ||
return s:gsub('([%(%)%%%.%[%]%*%+%-%?%^%$])', '%%%1') | |||
end | end | ||
Line 148: | Line 124: | ||
local nums = {} | local nums = {} | ||
for k | for k in pairs(t) do | ||
if type(k) == 'string' then | if type(k) == 'string' then | ||
local num = mw.ustring.match(k, pattern) | local num = mw.ustring.match(k, pattern) | ||
if num then | if num then | ||
Line 160: | Line 136: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- numData | -- numData | ||
-- | -- | ||
-- Given a table with keys like | -- Given a table with keys like {"foo1", "bar1", "foo2", "baz2"}, returns a table | ||
-- of subtables in the format | -- of subtables in the format | ||
-- { [1] = {foo = 'text', bar = 'text'}, [2] = {foo = 'text', baz = 'text'} } | -- {[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". | -- 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. | -- ipairs. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.numData(t, compress) | function p.numData(t, compress) | ||
checkType('numData', 1, t, 'table') | checkType('numData', 1, t, 'table') | ||
Line 201: | Line 175: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- compressSparseArray | -- compressSparseArray | ||
Line 209: | Line 182: | ||
-- ipairs. | -- ipairs. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.compressSparseArray(t) | function p.compressSparseArray(t) | ||
checkType('compressSparseArray', 1, t, 'table') | checkType('compressSparseArray', 1, t, 'table') | ||
Line 220: | Line 192: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- sparseIpairs | -- sparseIpairs | ||
Line 227: | Line 198: | ||
-- handle nil values. | -- handle nil values. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.sparseIpairs(t) | function p.sparseIpairs(t) | ||
checkType('sparseIpairs', 1, t, 'table') | checkType('sparseIpairs', 1, t, 'table') | ||
Line 244: | Line 214: | ||
end | end | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
-- size | -- size | ||
Line 251: | Line 220: | ||
-- but for arrays it is more efficient to use the # operator. | -- but for arrays it is more efficient to use the # operator. | ||
------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ||
function p.size(t) | function p.size(t) | ||
checkType('size', 1, t, 'table') | checkType('size', 1, t, 'table') | ||
local i = 0 | local i = 0 | ||
for | for _ in pairs(t) do | ||
i = i + 1 | i = i + 1 | ||
end | end | ||
return i | return i | ||
end | end | ||
local function defaultKeySort(item1, item2) | local function defaultKeySort(item1, item2) | ||
Line 268: | Line 234: | ||
if type1 ~= type2 then | if type1 ~= type2 then | ||
return type1 < type2 | return type1 < type2 | ||
elseif type1 == 'table' or type1 == 'boolean' or type1 == 'function' then | |||
return tostring(item1) < tostring(item2) | |||
else | |||
return item1 < item2 | return item1 < item2 | ||
end | end | ||
end | end | ||
------------------------------------------------------------------------------------ | |||
-- | -- keysToList | ||
-- | |||
-- Returns 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) | function p.keysToList(t, keySort, checked) | ||
if not checked then | if not checked then | ||
checkType('keysToList', 1, t, 'table') | checkType('keysToList', 1, t, 'table') | ||
checkTypeMulti('keysToList', 2, keySort, { 'function', 'boolean', 'nil' }) | checkTypeMulti('keysToList', 2, keySort, {'function', 'boolean', 'nil'}) | ||
end | end | ||
local | local arr = {} | ||
local index = 1 | local index = 1 | ||
for | for k in pairs(t) do | ||
arr[index] = k | |||
index = index + 1 | index = index + 1 | ||
end | end | ||
if keySort ~= false then | if keySort ~= false then | ||
keySort = type(keySort) == 'function' and keySort or defaultKeySort | keySort = type(keySort) == 'function' and keySort or defaultKeySort | ||
table.sort(arr, keySort) | |||
table.sort( | |||
end | end | ||
return | return arr | ||
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) | function p.sortedPairs(t, keySort) | ||
checkType('sortedPairs', 1, t, 'table') | checkType('sortedPairs', 1, t, 'table') | ||
checkType('sortedPairs', 2, keySort, 'function', true) | checkType('sortedPairs', 2, keySort, 'function', true) | ||
local | local arr = p.keysToList(t, keySort, true) | ||
local i = 0 | local i = 0 | ||
return function() | return function () | ||
i = i + 1 | i = i + 1 | ||
local key = | local key = arr[i] | ||
if key ~= nil then | if key ~= nil then | ||
return key, t[key] | return key, t[key] | ||
Line 321: | Line 291: | ||
end | end | ||
--[ | ------------------------------------------------------------------------------------ | ||
Returns true if all keys | -- isArray | ||
-- | -- | ||
function p. | -- 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] == nil then | |||
return false | |||
end | |||
end | |||
return true | |||
end | |||
------------------------------------------------------------------------------------ | |||
-- 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 | local i = 0 | ||
for | for _ in pairs(v) do | ||
i = i + 1 | i = i + 1 | ||
if | if v[i] == nil then | ||
return false | return false | ||
end | end | ||
Line 337: | Line 331: | ||
end | end | ||
-- { "a", "b", "c" } -> { a = 1, b = 2, c = 3 } | ------------------------------------------------------------------------------------ | ||
function p.invert( | -- invert | ||
checkType("invert", 1, | -- | ||
-- Transposes the keys and values in an array. For example, {"a", "b", "c"} -> | |||
-- {a = 1, b = 2, c = 3}. 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 = {} | local map = {} | ||
for i, v in ipairs( | for i, v in ipairs(arr) do | ||
map[v] = i | if not isNan(v) then | ||
map[v] = i | |||
end | |||
end | end | ||
return map | return map | ||
end | end | ||
-- | ------------------------------------------------------------------------------------ | ||
-- listToSet | |||
-- | -- | ||
function p.listToSet( | -- Creates a set from the array part of the table. Indexing the set by any of the | ||
checkType("listToSet", 1, | -- values of the array returns true. For example, {"a", "b", "c"} -> | ||
-- {a = true, b = true, c = true}. 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 = {} | local set = {} | ||
for _, | for _, v in ipairs(arr) do | ||
set[ | if not isNan(v) then | ||
set[v] = true | |||
end | |||
end | end | ||
return set | return set | ||
end | end | ||
-- | ------------------------------------------------------------------------------------ | ||
-- deepCopy | |||
-- | |||
-- Recursive deep copy function. Preserves identities of subtables. | |||
------------------------------------------------------------------------------------ | |||
local function _deepCopy(orig, includeMetatable, already_seen) | 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] | local copy = already_seen[orig] | ||
if copy ~= nil then | if copy ~= nil then | ||
Line 377: | Line 388: | ||
end | 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 | ||
end | end | ||
return copy | return copy | ||
end | end | ||
Line 400: | Line 407: | ||
function p.deepCopy(orig, noMetatable, already_seen) | function p.deepCopy(orig, noMetatable, already_seen) | ||
checkType("deepCopy", 3, already_seen, "table", true) | checkType("deepCopy", 3, already_seen, "table", true) | ||
return _deepCopy(orig, not noMetatable, already_seen or {}) | |||
return _deepCopy(orig, not noMetatable, already_seen) | |||
end | 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) | function p.sparseConcat(t, sep, i, j) | ||
local | local arr = {} | ||
local | local arr_i = 0 | ||
for _, v in p.sparseIpairs(t) do | for _, v in p.sparseIpairs(t) do | ||
arr_i = arr_i + 1 | |||
arr[arr_i] = v | |||
end | end | ||
return table.concat( | 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 [[Module:Exponential search]] 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 0 | |||
end | end | ||
-- | ------------------------------------------------------------------------------------ | ||
-- | -- inArray | ||
-- | -- | ||
-- a | -- 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") | ||
function p. | -- 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({unpack(array, fromIndex)}) do | |||
if v == searchElement then | |||
return true | |||
end | |||
end | |||
else | |||
for _, v in pairs(array) do | |||
if v == searchElement then | |||
return true | |||
end | |||
end | |||
end | end | ||
return | return false | ||
end | end | ||
function p. | ------------------------------------------------------------------------------------ | ||
-- 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 | ||
end | end | ||
return ret | |||
end | |||
------------------------------------------------------------------------------------ | |||
-- 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 | |||
end | |||
end | end | ||
return p | return p |
Latest revision as of 13:49, 18 August 2024
------------------------------------------------------------------------------------
-- 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.floor
local infinity = math.huge
local checkType = libraryUtil.checkType
local 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) == '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 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) == 'number' and v ~= v
end
------------------------------------------------------------------------------------
-- 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 ret
end
------------------------------------------------------------------------------------
-- 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 ret
end
------------------------------------------------------------------------------------
-- 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 nums
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 will return
-- {1, 3, 6}.
------------------------------------------------------------------------------------
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) == 'string' then
local num = mw.ustring.match(k, pattern)
if num then
nums[#nums + 1] = tonumber(num)
end
end
end
table.sort(nums)
return nums
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
-- 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 == '' then
-- Positional parameters match the blank string; put them at the start of the subtable instead.
prefix = 1
end
subtable[prefix] = v
ret[num] = subtable
else
local subtable = ret.other or {}
subtable[k] = v
ret.other = subtable
end
end
if compress then
local other = ret.other
ret = p.compressSparseArray(ret)
ret.other = other
end
return ret
end
------------------------------------------------------------------------------------
-- 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 ret
end
------------------------------------------------------------------------------------
-- 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
end
end
------------------------------------------------------------------------------------
-- 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 i
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
elseif type1 == 'table' or type1 == 'boolean' or type1 == 'function' then
return tostring(item1) < tostring(item2)
else
return item1 < item2
end
end
------------------------------------------------------------------------------------
-- keysToList
--
-- Returns 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 arr = {}
local index = 1
for k in pairs(t) do
arr[index] = k
index = index + 1
end
if keySort ~= false then
keySort = type(keySort) == 'function' and keySort or defaultKeySort
table.sort(arr, keySort)
end
return arr
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 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
end
end
------------------------------------------------------------------------------------
-- 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] == nil then
return false
end
end
return true
end
------------------------------------------------------------------------------------
-- 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] == nil then
return false
end
end
return true
end
------------------------------------------------------------------------------------
-- invert
--
-- Transposes the keys and values in an array. For example, {"a", "b", "c"} ->
-- {a = 1, b = 2, c = 3}. 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 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}. 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 set
end
------------------------------------------------------------------------------------
-- 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 copy
end
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{a, nil, c, d} => "acd"
-- sparseConcat{nil, b, c, d} => "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 [[Module:Exponential search]] 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 0
end
------------------------------------------------------------------------------------
-- 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({unpack(array, fromIndex)}) do
if v == searchElement then
return true
end
end
else
for _, v in pairs(array) do
if v == searchElement then
return true
end
end
end
return false
end
------------------------------------------------------------------------------------
-- 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 ret
end
------------------------------------------------------------------------------------
-- 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
end
end
return p