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Module:table (view source)

Revision as of 10:15, 14 August 2024

4,501 bytes added ,  14 August 2024
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]]
]]


local libraryUtil = require('libraryUtil')
local export = {}


local export = {}
local libraryUtil = require("libraryUtil")
local table = table


-- Define often-used variables and functions.
local floor = math.floor
local infinity = math.huge
local checkType = libraryUtil.checkType
local checkType = libraryUtil.checkType
local checkTypeMulti = libraryUtil.checkTypeMulti
local checkTypeMulti = libraryUtil.checkTypeMulti
local concat = table.concat
local format = string.format
local getmetatable = getmetatable
local insert = table.insert
local ipairs = ipairs
local is_callable = require("Module:fun").is_callable
local is_positive_integer -- defined as export.isPositiveInteger below
local keys_to_list -- defined as export.keysToList below
local next = next
local pairs = pairs
local rawequal = rawequal
local rawget = rawget
local setmetatable = setmetatable
local sort = table.sort
local string_sort = require("Module:collation").string_sort
local type = type
local infinity = math.huge


local function _check(funcName, expectType)
local function _check(funcName, expectType)
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return function(argIndex, arg, expectType, nilOk)
return function(argIndex, arg, expectType, nilOk)
if type(expectType) == "table" then
if type(expectType) == "table" then
checkTypeMulti(funcName, argIndex, arg, expectType, nilOk)
if not nilOk or arg ~= nil then
-- checkTypeMulti() doesn't accept a fifth `nilOk` argument, unlike the other check functions.
checkTypeMulti(funcName, argIndex, arg, expectType)
end
else
else
checkType(funcName, argIndex, arg, expectType, nilOk)
checkType(funcName, argIndex, arg, expectType, nilOk)
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end
end


--[[
--[==[
------------------------------------------------------------------------------------
Return true if the given value is a positive integer, and false if not. Although it doesn't operate on tables, it is
-- isPositiveInteger
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.
-- 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 export.isPositiveInteger(v)
function export.isPositiveInteger(v)
return type(v) == 'number' and v >= 1 and floor(v) == v and v < infinity
return type(v) == "number" and v >= 1 and v % 1 == 0 and v < infinity
end
end
is_positive_integer = export.isPositiveInteger


--[[
--[==[
------------------------------------------------------------------------------------
Return a clone of an object. If the object is 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.
-- isNan
]==]
--
function export.shallowcopy(orig)
-- This function returns true if the given number is a NaN value, and false
if type(orig) ~= "table" then
-- if not. Although it doesn't operate on tables, it is included here as it is
return orig
-- 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 export.isNan(v)
if type(v) == 'number' and tostring(v) == '-nan' then
return true
else
return false
end
end
end
local copy = {}
 
for k, v in pairs(orig) do
--[[
copy[k] = v
------------------------------------------------------------------------------------
-- shallowcopy
--
-- This returns a clone of an object. If the object is 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 export.shallowcopy(orig)
local orig_type = type(orig)
local copy
if orig_type == 'table' then
copy = {}
for orig_key, orig_value in pairs(orig) do
copy[orig_key] = orig_value
end
else -- number, string, boolean, etc
copy = orig
end
end
return copy
return copy
end
end


-- An alias for shallowcopy(); prefer shallowcopy().
do
function export.shallowClone(t)
local function rawpairs(t)
return export.shallowcopy(t)
return next, t
end
end
 
------------------------------------------------------------------------------------
-- deepcopy
--
-- Recursive deep copy function. Preserves copied identities of subtables.
-- A more powerful version of mw.clone, as it is able to clone recursive tables without getting into an infinite loop.
-- NOTE: protected metatables will not be copied (i.e. those hidden behind a __metatable metamethod), as they are not accessible by Lua's design. Instead, the output of the __metatable method will be used instead.
-- An exception is made for data loaded via mw.loadData, which has its metatable stripped by default. This is because it has a protected metatable, and the substitute metatable causes behaviour that is generally unwanted. This exception can be overridden by setting `rawCopy` to true.
-- If `noMetatable` is true, then metatables will not be present in the copy at all.
-- If `keepLoadedData` is true, then any data loaded via mw.loadData will not be copied, and the original will be used instead. This is useful in iterative contexts where it is necessary to copy data being destructively modified, because objects loaded via mw.loadData are immutable.
------------------------------------------------------------------------------------
 
function export.deepcopy(orig, noMetatable, rawCopy, keepLoadedData)
local already_seen = {}
local function dc(orig, includeMetatable)
local function make_copy(orig, memo, mt_flag, keep_loaded_data)
if keepLoadedData then
if type(orig) ~= "table" then
local mt = getmetatable(orig)
return orig
if mt and mt.mw_loadData then
end
return orig
local memoized = memo[orig]
end
if memoized ~= nil then
return memoized
end
end
if type(orig) == "table" then
local mt = getmetatable(orig)
if not already_seen[orig] then
local loaded_data = mt and mt.mw_loadData
local copy = {}
if loaded_data and keep_loaded_data then
already_seen[orig] = copy
memo[orig] = orig
for key, value in pairs(orig) do
copy[dc(key, includeMetatable)] = dc(value, includeMetatable)
end
if includeMetatable then
local mt = getmetatable(orig)
if type(mt) == "table" and (
(not mt.mw_loadData) or
(mt.mw_loadData and rawCopy)
) then  
setmetatable(copy, dc(mt, includeMetatable))
end
end
end
return already_seen[orig]
else
return orig
return orig
end
end
local copy = {}
memo[orig] = copy
for k, v in (loaded_data and pairs or rawpairs)(orig) do
copy[make_copy(k, memo, mt_flag, keep_loaded_data)] = make_copy(v, memo, mt_flag, keep_loaded_data)
end
if loaded_data then
return copy
elseif mt_flag == "keep" then
setmetatable(copy, mt)
elseif mt_flag ~= "none" then
setmetatable(copy, make_copy(mt, memo, mt_flag, keep_loaded_data))
end
return copy
end
end
return dc(orig, not noMetatable)
--[==[
Recursive deep copy function. Preserves copied identities of subtables.
A more powerful version of {mw.clone}, with customizable options.
* By default, metatables are copied, except for data loaded via mw.loadData (see below). If `metatableFlag` is set to "none", the copy will not have any metatables at all. Conversely, if `metatableFlag` is set to "keep", then the cloned table (and all its members) will have the exact same metatable as their original version.
* If `keepLoadedData` is true, then any data loaded via {mw.loadData} will not be copied, and the original will be used instead. This is useful in iterative contexts where it is necessary to copy data being destructively modified, because objects loaded via mw.loadData are immutable.
* Notes:
*# Protected metatables will not be copied (i.e. those hidden behind a __metatable metamethod), as they are not
  accessible by Lua's design. Instead, the output of the __metatable method will be used instead.
*# When iterating over the table, the __pairs metamethod is ignored, since this can prevent the table from being properly cloned.
*# Data loaded via mw.loadData is a special case in two ways: the metatable is stripped, because otherwise the cloned table throws errors when accessed; in addition, the __pairs metamethod is used, since otherwise the cloned table would be empty.]==]
function export.deepcopy(orig, metatableFlag, keepLoadedData)
return make_copy(orig, {}, metatableFlag, keepLoadedData)
end
end
end


--[[
--[==[
------------------------------------------------------------------------------------
Append any number of tables together and returns the result. Compare the Lisp expression {(append list1 list2 ...)}.
-- append
]==]
--
-- This appends any number of tables together and returns the result. Compare the Lisp
-- expression (append list1 list2 ...).
------------------------------------------------------------------------------------
--]]
function export.append(...)
function export.append(...)
local ret = {}
local ret, n = {}, 0
for i=1,select('#', ...) do
for i = 1, arg.n do
local argt = select(i, ...)
for _, v in ipairs(arg[i]) do
checkType('append', i, argt, 'table')
n = n + 1
for _, v in ipairs(argt) do
ret[n] = v
table.insert(ret, v)
end
end
end
end
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end
end


--[[
--[==[
------------------------------------------------------------------------------------
Extend an existing list by a new list, modifying the existing list in-place. Compare the Python expression
-- removeDuplicates
{list.extend(new_items)}.
--
 
-- This removes duplicate values from an array. Non-positive-integer keys are
`options` is an optional table of additional options to control the behavior of the operation. The following options are
-- ignored. The earliest value is kept, and all subsequent duplicate values are
recognized:
-- removed, but otherwise the array order is unchanged.
* `insertIfNot`: Use {export.insertIfNot()} instead of {table.insert()}, which ensures that duplicate items do not get
------------------------------------------------------------------------------------
  inserted (at the cost of an O((M+N)*N) operation, where M = #list and N = #new_items).
--]]
* `key`: As in {insertIfNot()}. Ignored otherwise.
* `pos`: As in {insertIfNot()}. Ignored otherwise.
]==]
function export.extendList(list, new_items, options)
local check = _check("extendList", "table")
check(1, list)
check(2, new_items)
check(3, options, true)
for _, item in ipairs(new_items) do
if options and options.insertIfNot then
export.insertIfNot(list, item, options)
else
insert(list, item)
end
end
end
 
--[==[
Remove 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.
-- -0, NaN and -NaN have special handling, as they can't be used as table keys.
]==]
function export.removeDuplicates(t)
function export.removeDuplicates(t)
checkType('removeDuplicates', 1, t, 'table')
checkType("removeDuplicates", 1, t, "table")
local isNan = export.isNan
local ret, n, seen, _neg_0, _pos_nan, _neg_nan = {}, 0, {}
local ret, exists = {}, {}
local index = 1
for _, v in ipairs(t) do
for _, v in ipairs(t) do
if isNan(v) then
local v_key = v
-- NaNs can't be table keys, and they are also unique, so we don't need to check existence.
-- -0
ret[index] = v
if v == 0 and 1 / v < 0 then
index = index + 1
_neg_0 = _neg_0 or {}
else
v_key = _neg_0
if not exists[v] then
-- NaN and -NaN.
ret[index] = v
elseif v ~= v then
index = index + 1
if format("%f", v) == "nan" then
exists[v] = true
_pos_nan = _pos_nan or {}
v_key = _pos_nan
else
_neg_nan = _neg_nan or {}
v_key = _neg_nan
end
end
end
if not seen[v_key] then
n = n + 1
ret[n] = v
seen[v_key] = true
end
end
end
end
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end
end


--[[
--[==[
------------------------------------------------------------------------------------
Given a table, return an array containing the numbers of any numerical keys that have non-nil values, sorted in
-- numKeys
numerical order.
--
]==]
-- 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 export.numKeys(t, checked)
function export.numKeys(t, checked)
if not checked then
if not checked then
checkType('numKeys', 1, t, 'table')
checkType("numKeys", 1, t, "table")
end
end
local isPositiveInteger = export.isPositiveInteger
local nums = {}
local nums = {}
local index = 1
local index = 1
for k, _ in pairs(t) do
for k in pairs(t) do
if isPositiveInteger(k) then
if is_positive_integer(k) then
nums[index] = k
nums[index] = k
index = index + 1
index = index + 1
end
end
end
end
table.sort(nums)
sort(nums)
return nums
return nums
end
end


--[==[
Return the maximum index of a table or array that possibly has holes in it, or 0 if there are no numerical keys in the
table.
]==]
function export.maxIndex(t)
function export.maxIndex(t)
checkType('maxIndex', 1, t, 'table')
local max = 0
local positiveIntegerKeys = export.numKeys(t)
for k in pairs(t) do
if positiveIntegerKeys[1] then
if is_positive_integer(k) and k > max then
return math.max(unpack(positiveIntegerKeys))
max = k
else
return 0 -- ???
end
end
 
--[[
------------------------------------------------------------------------------------
-- affixNums
--
-- This takes a table and returns an array containing the numbers of keys with the
-- specified prefix and suffix.
-- affixNums({a1 = 'foo', a3 = 'bar', a6 = 'baz'}, "a")
-- ↓
-- {1, 3, 6}.
------------------------------------------------------------------------------------
--]]
function export.affixNums(t, prefix, suffix)
local check = _check('affixNums')
check(1, t, 'table')
check(2, prefix, 'string', true)
check(3, suffix, 'string', true)
local function cleanPattern(s)
-- Cleans a pattern so that the magic characters ()%.[]*+-?^$ are interpreted literally.
s = s:gsub('([%(%)%%%.%[%]%*%+%-%?%^%$])', '%%%1')
return s
end
prefix = prefix or ''
suffix = suffix or ''
prefix = cleanPattern(prefix)
suffix = cleanPattern(suffix)
local pattern = '^' .. prefix .. '([1-9]%d*)' .. suffix .. '$'
local nums = {}
local index = 1
for k, _ in pairs(t) do
if type(k) == 'string' then
local num = mw.ustring.match(k, pattern)
if num then
nums[index] = tonumber(num)
index = index + 1
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 export.numData(t, compress)
local check = _check('numData')
check(1, t, 'table')
check(2, compress, 'boolean', true)
local ret = {}
for k, v in pairs(t) do
local prefix, num = tostring(k):match('^([^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
end
end
if compress then
return max
local other = ret.other
ret = export.compressSparseArray(ret)
ret.other = other
end
return ret
end
end


--[[
--[==[
------------------------------------------------------------------------------------
This takes an array with one or more nil values, and removes the nil values
-- compressSparseArray
while preserving the order, so that the array can be safely traversed with
--
ipairs.
-- 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 export.compressSparseArray(t)
function export.compressSparseArray(t)
checkType('compressSparseArray', 1, t, 'table')
checkType("compressSparseArray", 1, t, "table")
local ret = {}
local ret = {}
local index = 1
local index = 1
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end
end


--[[
--[==[
------------------------------------------------------------------------------------
This is an iterator for sparse arrays. It can be used like ipairs, but can handle nil values.
-- sparseIpairs
]==]
--
-- This is an iterator for sparse arrays. It can be used like ipairs, but can
-- handle nil values.
------------------------------------------------------------------------------------
--]]
function export.sparseIpairs(t)
function export.sparseIpairs(t)
checkType('sparseIpairs', 1, t, 'table')
checkType("sparseIpairs", 1, t, "table")
local nums = export.numKeys(t)
local nums = export.numKeys(t)
local i = 0
local i = 0
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end
end


--[[
--[==[
------------------------------------------------------------------------------------
This returns the size of a key/value pair table. It will also work on arrays, but for arrays it is more efficient to
-- size
use the # operator.
--
]==]
-- 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 export.size(t)
function export.size(t)
checkType('size', 1, t, 'table')
checkType("size", 1, t, "table")
local i = 0
local i = 0
for _ in pairs(t) do
for _ in pairs(t) do
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end
end


--[[
--[==[
-- This returns the length of a table, or the first integer key n counting from
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 metamethods are involved. Intended to be used on data loaded with mw.loadData. For other tables, use #.
-- 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 export.length(t)
function export.length(t)
local i = 0
local i = 0
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end
end


--[[
Recursively compare two values that may be tables, including tables with
nested tables as values. Return true if both values are structurally equal.
Note that this handles arbitary levels of nesting. If all tables are known
to be lists (with only integral keys), use export.deepEqualsList, which will
be more efficient.


If `includeMetatables` is true, then metatables will also be compared. However,
do
by default, metatables from mw.loadData will not be included in this comparison.
local function is_equivalent(a, b, memo, include_mt)
This is because the metatable changes each time mw.loadData is used, even if
-- Raw equality check.
it is used on the same data. This can be overridden by setting `rawCompare` to
if rawequal(a, b) then
true.
return true
]]
-- If not equal, a and b can only be equivalent if they're both tables.
 
elseif not (type(a) == "table" and type(b) == "table") then
function export.deepEquals(x, y, includeMetatables, rawCompare)
return false
local already_seen = {}
end
-- If a and b have been compared before, they must be equivalent.
-- This strips metatables only from data loaded via mw.loadData.
local memo_a = memo[a]
if includeMetatables and not rawCompare then
if not memo_a then
x = export.deepcopy(x)
memo[a] = {[b] = true}
y = export.deepcopy(y)
elseif memo_a[b] then
end
return true
else
local function de(x, y)
memo_a[b] = true
if type(x) == "table" and type(y) == "table" then
end
-- Two tables are the same if they have the same number of
local memo_b = memo[b]
-- elements and all keys that are present in one of the tables
if not memo_b then
-- compare equal to the corresponding keys in the other table,
memo[b] = {[a] = true}
-- using structural comparison.
else -- We know memo_b won't have a, since memo_a didn't have b.
-- If an element of x is a table, then its table in `already_seen`
memo_b[a] = true
-- is checked for y (which means they have been compared before).
end
-- If so, immediately iterate to avoid duplicated work. This avoids
-- If include_mt is set, check the metatables are equivalent.
-- infinite loops.
if (
if not already_seen[x] then
include_mt and
already_seen[x] = {}
not is_equivalent(getmetatable(a), getmetatable(b), memo, true)
if not already_seen[x][y] then
) then
already_seen[x][y] = true
return false
local sizex = 0
end
for key, value in pairs(x) do
-- Fast check: loop over keys in a, checking if an equivalent value exists at the same key in b. Any tables-as-keys are set aside for the laborious check instead.
if not de(value, y[key]) then
local tablekeys_a, tablekeys_b, kb
return false
for ka, va in next, a do
end
if type(ka) == "table" then
sizex = sizex + 1
if not tablekeys_a then
end
tablekeys_a = {[ka] = va}
if includeMetatables and not de(getmetatable(x), getmetatable(y)) then
else
return false
tablekeys_a[ka] = va
end
end
local sizey = export.size(y)
else
if sizex ~= sizey then
local vb = rawget(b, ka)
return false
-- Faster to avoid recursion if possible, as we know va is not nil.
end
if vb == nil or not is_equivalent(va, vb, memo, include_mt) then
return false
end
end
-- Iterate over b simultaneously (to check it's the same size and to grab any tables-as-keys for the laborious check), but also separately (since it might iterate in a different order, as this is unpredictable in Lua).
local vb
kb, vb = next(b, kb)
-- Fail if b runs out of key/value pairs too early.
if kb == nil then
return false
elseif type(kb) == "table" then
if not tablekeys_b then
tablekeys_b = {[kb] = vb}
else
tablekeys_b[kb] = vb
end
end
end
end
end
-- Fail if there are too many key/value pairs in b.
if next(b, kb) ~= nil then
return false
-- If tablekeys_a == tablekeys_b they must be both nil, meaning there are no tables-as-keys to check, so success.
elseif tablekeys_a == tablekeys_b then
return true
return true
-- If only one them exists, then the tables can't be equivalent.
elseif not (tablekeys_a and tablekeys_b) then
return false
end
-- Laborious check: for each table-as-key in tablekeys_a, loop over tablekeys_b looking for an equivalent key/value pair.
for ka, va in next, tablekeys_a do
local kb
while true do
local vb
kb, vb = next(tablekeys_b, kb)
-- Fail if no equivalent is found.
if kb == nil then
return false
elseif (
is_equivalent(ka, kb, memo, include_mt) and
is_equivalent(va, vb, memo, include_mt)
) then
-- Remove match to prevent double-matching (and for speed).
tablekeys_b[kb] = nil
break
end
end
end
end
return x == y
-- Success if tablekeys_b is now empty.
return next(tablekeys_b) == nil
end
end
return de(x, y)
--[==[
Recursively compare two values that may be tables, and returns true if all key-value pairs are structurally equivalent. Note that this handles arbitrary nesting of subtables (including recursive nesting) to any depth, for keys as well as values.
 
If `include_mt` is true, then metatables are also compared.]==]
function export.deepEquals(a, b, include_mt)
return is_equivalent(a, b, {}, include_mt)
end
end
end


--[[
do
Recursively compare two values that may be lists (i.e. tables with integral
local function get_nested(a, b, ...)
keys), including lists with nested lists as values. Return true if both values
if a == nil then
are structurally equal. Note that this handles arbitary levels of nesting.
return nil
Results are undefined if tables with non-integral keys are present anywhere in
elseif ... ~= nil then
either structure; if that may be the case, use export.deepEquals, which will
return get_nested(a[b], ...)
handle such tables correctly but be less efficient on lists than
end
export.deepEqualsList.
return a[b]
]]
end
function export.deepEqualsList(x, y)
local already_seen = {}
local function de(x, y)
--[==[
if type(x) == "table" and type(y) == "table" then
Given a table and an arbitrary number of keys, will successively access subtables using each key in turn, returning the value at the final key. For example, if {t} is { {[1] = {[2] = {[3] = "foo"}}}}, {export.getNested(t, 1, 2, 3)} will return {"foo"}.
if not already_seen[x] then
already_seen[x] = {}
If no subtable exists for a given key value, returns nil, but will throw an error if a non-table is found at an intermediary key.
if not already_seen[x][y] then
]==]
already_seen[x][y] = true
function export.getNested(a, ...)
if #x ~= #y then
if a == nil or ... == nil then
return false
error("Must provide a table and at least one key.")
end  
end
for key, value in pairs(x) do
return get_nested(a, ...)
if not de(value, y[key]) then
end
return false
end
end
 
end
do
end
local function set_nested(a, b, c, ...)
end
if ... == nil then
return true
a[c] = b
return
end
local t = a[c]
if t == nil then
t = {}
a[c] = t
end
end
return x == y
return set_nested(t, b, ...)
end
end
return de(x, y)
--[==[
Given a table, value and an arbitrary number of keys, will successively access subtables using each key in turn, and sets the value at the final key. For example, if {t} is { {} }, {export.setNested(t, "foo", 1, 2, 3)} will modify {t} to { {[1] = {[2] = {[3] = "foo"} } } }.
If no subtable exists for a given key value, one will be created, but the function will throw an error if a non-table value is found at an intermediary key.
Note: the parameter order (table, value, keys) differs from functions like rawset, because the number of keys can be arbitrary. This is to avoid situations where an additional argument must be appended to arbitrary lists of variables, which can be awkward and error-prone: for example, when handling variable arguments ({{lua|...}}) or function return values.
]==]
function export.setNested(a, b, ...)
if a == nil or b == nil or ... == nil then
error("Must provide a table, value and at least one key.")
end
return set_nested(a, b, ...)
end
end
end


--[[
--[==[
Given a list and a value to be found, return true if the value is in the array
Given a list and a value to be found, return true if the value is in the array
portion of the list. Comparison is by value, using `deepEquals`.
portion of the list. Comparison is by value, using `deepEquals`.
]==]
function export.contains(list, x, options)
local check = _check("contains", "table")
check(1, list)
check(3, options, true)


NOTE: This used to do shallow comparison by default and accepted a third
if options and options.key then
'deepCompare' param to do deep comparison. This param is still accepted but now
x = options.key(x)
ignored.
end
]]
function export.contains(list, x)
checkType('contains', 1, list, 'table')
for _, v in ipairs(list) do
for _, v in ipairs(list) do
if options and options.key then
v = options.key(v)
end
if export.deepEquals(v, x) then return true end
if export.deepEquals(v, x) then return true end
end
end
Line 509: Line 474:
end
end


--[[
--[==[
Given a general table and a value to be found, return true if the value is in
Given a general table and a value to be found, return true if the value is in
either the array or hashmap portion of the table. Comparison is by value, using
either the array or hashmap portion of the table. Comparison is by value, using
Line 515: Line 480:


NOTE: This used to do shallow comparison by default and accepted a third
NOTE: This used to do shallow comparison by default and accepted a third
'deepCompare' param to do deep comparison. This param is still accepted but now
"deepCompare" param to do deep comparison. This param is still accepted but now
ignored.
ignored.
]]
]==]
function export.tableContains(tbl, x)
function export.tableContains(tbl, x)
checkType('tableContains', 1, tbl, 'table')
checkType("tableContains", 1, tbl, "table")
for _, v in pairs(tbl) do
for _, v in pairs(tbl) do
if export.deepEquals(v, x) then return true end
if export.deepEquals(v, x) then return true end
Line 526: Line 491:
end
end


--[[
--[==[
Given a list and a value to be inserted, append or insert the value if not
Given a `list` and an `item` to be inserted, append the value to the end of the list if not already present
already present in the list. Comparison is by value, using `deepEquals`.
(or insert at an arbitrary position, if `options.pos` is given; see below). Comparison is by value, using {deepEquals}.
Appends to the end, like the default behavior of table.insert(), unless `pos`
is given, in which case insertion happens at position `pos` (i.e. before the
existing item at position `pos`).


NOTE: The order of `item` and `pos` is reversed in comparison to table.insert(),
`options` is an optional table of additional options to control the behavior of the operation. The following options are
which uses `table.insert(list, item)` to insert at the end but
recognized:
`table.insert(list, pos, item)` to insert at position POS.
* `pos`: Position at which insertion happens (i.e. before the existing item at position `pos`).
* `key`: Function of one argument to return a comparison key, as with {deepEquals}. The key function is applied to both
        `item` and the existing item in `list` to compare against, and the comparison is done against the results.
        This is useful when inserting a complex structure into an existing list while avoiding duplicates.


NOTE: This used to do shallow comparison by default and accepted a fourth
For compatibility, `pos` can be specified directly as the third argument in place of `options`, but this is not
'deepCompare' param to do deep comparison. This param is still accepted but now
recommended for new code.
ignored.
 
]]
NOTE: This function is O(N) in the size of the existing list. If you use this function in a loop to insert several
function export.insertIfNot(list, item, pos)
items, you will get O(M*(M+N)) behavior, effectively O((M+N)^2). Thus it is not recommended to use this unless you are
if not export.contains(list, item) then
sure the total number of items will be small. (An alternative for large lists is to insert all the items without
if pos then
checking for duplicates, and use {removeDuplicates()} at the end.)
table.insert(list, pos, item)
]==]
function export.insertIfNot(list, item, options)
local check = _check("insertIfNot")
check(1, list, "table")
check(3, options, {"table", "number"}, true)
 
if type(options) == "number" then
options = {pos = options}
end
if not export.contains(list, item, options) then
if options and options.pos then
insert(list, options.pos, item)
else
else
table.insert(list, item)
insert(list, item)
end
end
end
end
end
end


--[[
--[==[
Finds key for specified value in a given table.
Finds key for specified value in a given table. Roughly equivalent to reversing the key-value pairs in the table:
Roughly equivalent to reversing the key-value pairs in the table –
* {reversed_table = { [value1] = key1, [value2] = key2, ... }}
reversed_table = { [value1] = key1, [value2] = key2, ... }
and then returning {reversed_table[valueToFind]}.
– and then returning reversed_table[valueToFind].
 
The value can only be a string or a number (not nil, a boolean, a table, or a function).
The value can only be a string or a number
 
(not nil, a boolean, a table, or a function).
Only reliable if there is just one key with the specified value. Otherwise, the function returns the first key found,
and the output is unpredictable.
Only reliable if there is just one key with the specified value.
]==]
Otherwise, the function returns the first key found,
and the output is unpredictable.
]]
function export.keyFor(t, valueToFind)
function export.keyFor(t, valueToFind)
local check = _check('keyFor')
local check = _check("keyFor")
check(1, t, 'table')
check(1, t, "table")
check(2, valueToFind, { 'string', 'number' })
check(2, valueToFind, {"string", "number"})
for key, value in pairs(t) do
for key, value in pairs(t) do
Line 578: Line 551:
end
end


--[[
do
The default sorting function used in export.keysToList if no keySort
-- The default sorting function used in export.keysToList if no keySort is defined.
is defined.
local function defaultKeySort(key1, key2)
]]
-- "number" < "string", so numbers will be sorted before strings.
local function defaultKeySort(key1, key2)
local type1, type2 = type(key1), type(key2)
-- "number" < "string", so numbers will be sorted before strings.
if type1 ~= type2 then
local type1, type2 = type(key1), type(key2)
return type1 < type2
if type1 ~= type2 then
end
return type1 < type2
-- string_sort fixes a bug in < whereby all codepoints above U+FFFF are treated as equal.
else
return string_sort(key1, key2)
return key1 < key2
end
end
end
 
--[==[
--[[
Return a list of the keys in a table, sorted using either the default table.sort function or a custom keySort function.
Returns a list of the keys in a table, sorted using either the default
table.sort function or a custom keySort function.
If there are only numerical keys, numKeys is probably more efficient.
If there are only numerical keys, numKeys is probably more efficient.
]]
]==]
function export.keysToList(t, keySort, checked)
function export.keysToList(t, keySort, checked)
if not checked then
if not checked then
local check = _check('keysToList')
local check = _check("keysToList")
check(1, t, 'table')
check(1, t, "table")
check(2, keySort, 'function', true)
check(2, keySort, "function", true)
end
local list, i = {}, 0
for key in pairs(t) do
i = i + 1
list[i] = key
end
-- Use specified sort function, or otherwise defaultKeySort.
sort(list, keySort or defaultKeySort)
return list
end
end
keys_to_list = export.keysToList
local list = {}
local index = 1
for key, _ in pairs(t) do
list[index] = key
index = index + 1
end
-- Place numbers before strings, otherwise sort using <.
if not keySort then
keySort = defaultKeySort
end
table.sort(list, keySort)
return list
end
end


--[[
--[==[
Iterates through a table, with the keys sorted using the keysToList function.
Iterates through a table, with the keys sorted using the keysToList function. If there are only numerical keys,
If there are only numerical keys, sparseIpairs is probably more efficient.
sparseIpairs is probably more efficient.
]]
]==]
function export.sortedPairs(t, keySort)
function export.sortedPairs(t, keySort)
local check = _check('keysToList')
local check = _check("keysToList")
check(1, t, 'table')
check(1, t, "table")
check(2, keySort, 'function', true)
check(2, keySort, "function", true)
local list = export.keysToList(t, keySort, true)
local list, i = keys_to_list(t, keySort, true), 0
local i = 0
return function()
return function()
i = i + 1
i = i + 1
Line 638: Line 604:
if key ~= nil then
if key ~= nil then
return key, t[key]
return key, t[key]
else
return nil, nil
end
end
end
end
end
end


function export.reverseIpairs(list)
do
checkType('reverse_ipairs', 1, list, 'table')
local function iter(t, i)
local i = #list + 1
return function()
i = i - 1
i = i - 1
if list[i] ~= nil then
if i > 0 then
return i, list[i]
return i, t[i]
else
return nil, nil
end
end
end
function export.reverseIpairs(t)
checkType("reverseIpairs", 1, t, "table")
-- Not safe to use #t, as it can be unpredictable if there is a hash part.
local i = 0
repeat
i = i + 1
until t[i] == nil
return iter, t, i
end
end
end
end
--[[
A set of functions that, given an array and function, iterate through the array applying that function.
`reduce` applies func(r, k, v), and returns the result, where r is the value calculated so far, k is an index, and v is the value at index k.  For example, reduce(array, function(a, b) return a + b end) will return the sum of `array`.
`apply` applies func(k, v), and returns the modified array. For example, apply(array, function(a) return 2*a end) will return an array where each member of `array` has been doubled.
`all` returns whether func(k, v) is true for all iterations.
`any` returns whether func(k, v) is true for at least one iteration.
Optional arguments:
i: start index; negative values count from the end of the array
j: end index; negative values count from the end of the array
s: step increment
These must be non-zero integers.
The function will determine where to iterate from, whether to iterate forwards or backwards and by how much, based on these inputs (see examples below for default behaviours).
Examples:
No values for i, j or s results in forward iteration from the start to the end in steps of 1 (the default).
s=-1 results in backward iteration from the end to the start in steps of 1.
i=7, j=3 results in backward iteration from indices 7 to 3 in steps of 1 (i.e. s=-1).
j=-3 results in forward iteration from the start to the 3rd last index.
j=-3, s=-1 results in backward iteration from the end to the 3rd last index.
Note: directionality generally only matters for `reduce`, but values of s > 1 (or s < -1) still affect the return value of `apply`.
]]


local function getIteratorValues(i, j , s, list)
local function getIteratorValues(i, j , s, list)
Line 693: Line 640:
return i, j, s
return i, j, s
end
end
--[==[
Given an array `list` and function `func`, iterate through the array applying {func(r, k, v)}, and returning the result,
where `r` is the value calculated so far, `k` is an index, and `v` is the value at index `k`. For example,
{reduce(array, function(a, b) return a + b end)} will return the sum of `array`.
Optional arguments:
* `i`: start index; negative values count from the end of the array
* `j`: end index; negative values count from the end of the array
* `s`: step increment
These must be non-zero integers. The function will determine where to iterate from, whether to iterate forwards or
backwards and by how much, based on these inputs (see examples below for default behaviours).
Examples:
# No values for i, j or s results in forward iteration from the start to the end in steps of 1 (the default).
# s=-1 results in backward iteration from the end to the start in steps of 1.
# i=7, j=3 results in backward iteration from indices 7 to 3 in steps of 1 (i.e. s=-1).
# j=-3 results in forward iteration from the start to the 3rd last index.
# j=-3, s=-1 results in backward iteration from the end to the 3rd last index.
Note: directionality generally only matters for `reduce`, but values of s > 1 (or s < -1) still affect the return value
of `apply`.
]==]


function export.reduce(list, func, i, j, s)
function export.reduce(list, func, i, j, s)
Line 703: Line 672:
end
end


--[==[
Given an array `list` and function `func`, iterate through the array applying {func(k, v)} (where `k` is an index, and
`v` is the value at index `k`), and return an array of the resulting values. For example,
{apply(array, function(a) return 2*a end)} will return an array where each member of `array` has been doubled.
Optional arguments:
* `i`: start index; negative values count from the end of the array
* `j`: end index; negative values count from the end of the array
* `s`: step increment
These must be non-zero integers. The function will determine where to iterate from, whether to iterate forwards or
backwards and by how much, based on these inputs (see examples below for default behaviours).
Examples:
# No values for i, j or s results in forward iteration from the start to the end in steps of 1 (the default).
# s=-1 results in backward iteration from the end to the start in steps of 1.
# i=7, j=3 results in backward iteration from indices 7 to 3 in steps of 1 (i.e. s=-1).
# j=-3 results in forward iteration from the start to the 3rd last index.
# j=-3, s=-1 results in backward iteration from the end to the 3rd last index.
Note: directionality makes the most difference for `reduce`, but values of s > 1 (or s < -1) still affect the return
value of `apply`.
]==]
function export.apply(list, func, i, j, s)
function export.apply(list, func, i, j, s)
local modified_list = export.deepcopy(list)
local modified_list = export.deepcopy(list)
Line 712: Line 702:
end
end


--[==[
Given an array `list` and function `func`, iterate through the array applying {func(k, v)} (where `k` is an index, and
`v` is the value at index `k`), and returning whether the function is true for all iterations.
Optional arguments:
* `i`: start index; negative values count from the end of the array
* `j`: end index; negative values count from the end of the array
* `s`: step increment
These must be non-zero integers. The function will determine where to iterate from, whether to iterate forwards or
backwards and by how much, based on these inputs (see examples below for default behaviours).
Examples:
# No values for i, j or s results in forward iteration from the start to the end in steps of 1 (the default).
# s=-1 results in backward iteration from the end to the start in steps of 1.
# i=7, j=3 results in backward iteration from indices 7 to 3 in steps of 1 (i.e. s=-1).
# j=-3 results in forward iteration from the start to the 3rd last index.
# j=-3, s=-1 results in backward iteration from the end to the 3rd last index.
]==]
function export.all(list, func, i, j, s)
function export.all(list, func, i, j, s)
i, j, s = getIteratorValues(i, j , s, list)
i, j, s = getIteratorValues(i, j , s, list)
Line 722: Line 730:
end
end


--[==[
Given an array `list` and function `func`, iterate through the array applying {func(k, v)} (where `k` is an index, and
`v` is the value at index `k`), and returning whether the function is true for at least one iteration.
Optional arguments:
* `i`: start index; negative values count from the end of the array
* `j`: end index; negative values count from the end of the array
* `s`: step increment
These must be non-zero integers. The function will determine where to iterate from, whether to iterate forwards or
backwards and by how much, based on these inputs (see examples below for default behaviours).
Examples:
# No values for i, j or s results in forward iteration from the start to the end in steps of 1 (the default).
# s=-1 results in backward iteration from the end to the start in steps of 1.
# i=7, j=3 results in backward iteration from indices 7 to 3 in steps of 1 (i.e. s=-1).
# j=-3 results in forward iteration from the start to the 3rd last index.
# j=-3, s=-1 results in backward iteration from the end to the 3rd last index.
]==]
function export.any(list, func, i, j, s)
function export.any(list, func, i, j, s)
i, j, s = getIteratorValues(i, j , s, list)
i, j, s = getIteratorValues(i, j , s, list)
Line 732: Line 758:
end
end


--[=[
--[==[
Joins an array with serial comma and serial conjunction, normally "and".
Joins an array with serial comma and serial conjunction, normally {"and"}. An improvement on {mw.text.listToText},
An improvement on mw.text.listToText, which doesn't properly handle serial
which doesn't properly handle serial commas.
commas.
 
Options:
Options:
* `conj`: Conjunction to use; defaults to {"and"}.
- conj
* `italicizeConj`: Italicize conjunction: for [[Module:also]]
Conjunction to use; defaults to "and".
* `dontTag`: Don't tag the serial comma and serial {"and"}. For error messages, in which HTML cannot be used.
- italicizeConj
]==]
Italicize conjunction: for [[Module:also]]
- dontTag
Don't tag the serial comma and serial "and". For error messages, in
which HTML cannot be used.
]=]
function export.serialCommaJoin(seq, options)
function export.serialCommaJoin(seq, options)
local check = _check("serialCommaJoin", "table")
local check = _check("serialCommaJoin", "table")
Line 772: Line 793:
return seq[1] .. " " .. conj .. " " .. seq[2]
return seq[1] .. " " .. conj .. " " .. seq[2]
else
else
local comma = options.dontTag and "," or '<span class="serial-comma">,</span>'
local comma = options.dontTag and "," or "<span class=\"serial-comma\">,</span>"
conj = options.dontTag and ' ' .. conj .. " " or '<span class="serial-and"> ' .. conj .. '</span> '
conj = options.dontTag and " " .. conj .. " " or "<span class=\"serial-and\"> " .. conj .. "</span> "
return table.concat(seq, ", ", 1, length - 1) ..
return concat(seq, ", ", 1, length - 1) ..
comma .. conj .. seq[length]
comma .. conj .. seq[length]
end
end
end
end


--[[
--[==[
Concatenates all values in the table that are indexed by a number, in order.
Concatenate all values in the table that are indexed by a number, in order.
sparseConcat{ a, nil, c, d }  =>  "acd"
* {sparseConcat{ a, nil, c, d }}  =>  {"acd"}
sparseConcat{ nil, b, c, d }  =>  "bcd"
* {sparseConcat{ nil, b, c, d }}  =>  {"bcd"}
]]
]==]
function export.sparseConcat(t, sep, i, j)
function export.sparseConcat(t, sep, i, j)
local list = {}
local list = {}
Line 793: Line 814:
end
end
return table.concat(list, sep, i, j)
return concat(list, sep, i, j)
end
end


--[[
--[==[
Values of numberic keys in array portion of table are reversed:
Values of numeric keys in array portion of table are reversed: { { "a", "b", "c" }} -> { { "c", "b", "a" }}
{ "a", "b", "c" } -> { "c", "b", "a" }
]==]
--]]
function export.reverse(t)
function export.reverse(t)
checkType("reverse", 1, t, "table")
checkType("reverse", 1, t, "table")
-- Not safe to use #t, as it can be unpredictable if there is a hash part.
local new_t = {}
local ret, base = {}, 0
local new_t_i = 1
repeat
for i = #t, 1, -1 do
base = base + 1
new_t[new_t_i] = t[i]
until t[base] == nil
new_t_i = new_t_i + 1
for i = base - 1, 1, -1 do
ret[base - i] = t[i]
end
end
return new_t
return ret
end
end


function export.reverseConcat(t, sep, i, j)
function export.reverseConcat(t, sep, i, j)
return table.concat(export.reverse(t), sep, i, j)
return concat(export.reverse(t), sep, i, j)
end
end


-- { "a", "b", "c" } -> { a = 1, b = 2, c = 3 }
--[==[
Invert an array. For example, {invert({ "a", "b", "c" })} -> { { a = 1, b = 2, c = 3 }}
]==]
function export.invert(array)
function export.invert(array)
checkType("invert", 1, array, "table")
checkType("invert", 1, array, "table")
Line 828: Line 851:
end
end


--[[
--[==[
{ "a", "b", "c" } -> { ["a"] = true, ["b"] = true, ["c"] = true }
Convert `list` (a table with a list of values) into a set (a table where those values are keys instead). This is a useful
--]]
way to create a fast lookup table, since looking up a table key is much, much faster than iterating over the whole list
function export.listToSet(t)
to see if it contains a given value.
checkType("listToSet", 1, t, "table")
 
By default, each item is given the value true. If the optional parameter `value` is a function or functor, then the value
local set = {}
for each item is determined by calling it with the item key as the first parameter, plus any additional arguments passed
for _, item in ipairs(t) do
to {listToSet}; if value is anything else, then it is used as the fixed value for every item.
set[item] = true
]==]
function export.listToSet(list, value, ...)
checkType("listToSet", 1, list, "table")
local set, i = {}, 0
if value == nil then
value = true
elseif is_callable(value) then
-- Separate loop avoids an "is callable" lookup each iteration.
while true do
i = i + 1
local item = list[i]
if item == nil then
return set
end
set[item] = value(item, ...)
end
end
while true do
i = i + 1
local item = list[i]
if item == nil then
return set
end
set[item] = value
end
end
return set
end
end


--[[
--[==[
Returns true if all keys in the table are consecutive integers starting at 1.
Return true if all keys in the table are consecutive integers starting at 1.
--]]
]==]
function export.isArray(t)
function export.isArray(t)
checkType("isArray", 1, t, "table")
checkType("isArray", 1, t, "table")
Line 857: Line 902:
end
end


--[[
--[==[
Add a list of aliases for a given key to a table. The aliases must be given as a table.
Add a list of aliases for a given key to a table. The aliases must be given as a table.
--]]
]==]
 
function export.alias(t, k, aliases)
function export.alias(t, k, aliases)
for _, alias in pairs(aliases) do
for _, alias in pairs(aliases) do
Retrieved from "https://linguifex.com/wiki/Special:MobileDiff/376376"

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