Module:table: Difference between revisions

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Module:table (view source)

Revision as of 14:50, 3 May 2023

5,264 bytes added ,  3 May 2023
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--[[
--[[
------------------------------------------------------------------------------------
------------------------------------------------------------------------------------
-- shallowClone
-- shallowcopy
--
--
-- This returns a clone of a table. The value returned is a new table, but all
-- This returns a clone of an object. If the object is a table, the value
-- subtables and functions are shared. Metamethods are respected, but the returned
-- returned is a new table, but all subtables and functions are shared.
-- table will have no metatable of its own.
-- Metamethods are respected, but the returned table will have no metatable of
-- its own.
------------------------------------------------------------------------------------
------------------------------------------------------------------------------------
--]]
--]]
function export.shallowClone(t)
local ret = {}
for k, v in pairs(t) do
ret[k] = v
end
return ret
end
--[[
Shallow copy
]]
function export.shallowcopy(orig)
function export.shallowcopy(orig)
local orig_type = type(orig)
local orig_type = type(orig)
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end
end


--[[
-- An alias for shallowcopy(); prefer shallowcopy().
Recursive deep copy function
function export.shallowClone(t)
Equivalent to mw.clone?
return export.shallowcopy(t)
]]
end
local function deepcopy(orig, includeMetatable, already_seen)
 
-- Stores copies of tables indexed by the original table.
------------------------------------------------------------------------------------
already_seen = already_seen or {}
-- 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 copy = already_seen[orig]
local function dc(orig, includeMetatable)
if copy ~= nil then
if keepLoadedData then
return copy
local mt = getmetatable(orig)
end
if mt and mt.mw_loadData then
return orig
if type(orig) == 'table' then
end
copy = {}
for orig_key, orig_value in pairs(orig) do
copy[deepcopy(orig_key, includeMetatable, already_seen)] = deepcopy(orig_value, includeMetatable, already_seen)
end
end
already_seen[orig] = copy
if type(orig) == "table" then
if not already_seen[orig] then
if includeMetatable then
local copy = {}
local mt = getmetatable(orig)
already_seen[orig] = copy
if mt ~= nil then
for key, value in pairs(orig) do
local mt_copy = deepcopy(mt, includeMetatable, already_seen)
copy[dc(key, includeMetatable)] = dc(value, includeMetatable)
setmetatable(copy, mt_copy)
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
end
return already_seen[orig]
else
return orig
end
end
else -- number, string, boolean, etc
copy = orig
end
end
return copy
end
function export.deepcopy(orig, noMetatable, already_seen)
checkType("deepcopy", 3, already_seen, "table", true)
return deepcopy(orig, not noMetatable, already_seen)
return dc(orig, not noMetatable)
end
end


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-- append
-- append
--
--
-- This appends two tables together and returns the result. Compare the Lisp
-- This appends any number of tables together and returns the result. Compare the Lisp
-- expression (append list1 list2).
-- expression (append list1 list2 ...).
------------------------------------------------------------------------------------
------------------------------------------------------------------------------------
--]]
--]]
function export.append(t1, t2)
function export.append(...)
checkType('append', 1, t1, 'table')
checkType('append', 2, t2, 'table')
local ret = {}
local ret = {}
for _, v in ipairs(t1) do
for i=1,select('#', ...) do
table.insert(ret, v)
local argt = select(i, ...)
end
checkType('append', i, argt, 'table')
for _, v in ipairs(t2) do
for _, v in ipairs(argt) do
table.insert(ret, v)
table.insert(ret, v)
end
end
end
return ret
return ret
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be more efficient.
be more efficient.


NOTE: This is *NOT* smart enough to properly handle cycles; in such a case, it
If `includeMetatables` is true, then metatables will also be compared. However,
will get into an infinite loop.
by default, metatables from mw.loadData will not be included in this comparison.
This is because the metatable changes each time mw.loadData is used, even if
it is used on the same data. This can be overridden by setting `rawCompare` to
true.
]]
]]
function export.deepEquals(x, y)
 
if type(x) == "table" and type(y) == "table" then
function export.deepEquals(x, y, includeMetatables, rawCompare)
-- Two tables are the same if they have the same number of elements
local already_seen = {}
-- and all keys that are present in one of the tables compare equal
-- to the corresponding keys in the other table, using structural
-- This strips metatables only from data loaded via mw.loadData.
-- comparison.
if includeMetatables and not rawCompare then
local sizex = 0
x = export.deepcopy(x)
for key, value in pairs(x) do
y = export.deepcopy(y)
if not export.deepEquals(value, y[key]) then
end
return false
local function de(x, y)
if type(x) == "table" and type(y) == "table" then
-- Two tables are the same if they have the same number of
-- elements and all keys that are present in one of the tables  
-- compare equal to the corresponding keys in the other table,  
-- using structural comparison.
-- If an element of x is a table, then its table in `already_seen`
-- is checked for y (which means they have been compared before).
-- If so, immediately iterate to avoid duplicated work. This avoids
-- infinite loops.
if not already_seen[x] then
already_seen[x] = {}
if not already_seen[x][y] then
already_seen[x][y] = true
local sizex = 0
for key, value in pairs(x) do
if not de(value, y[key]) then
return false
end
sizex = sizex + 1
end
if includeMetatables and not de(getmetatable(x), getmetatable(y)) then
return false
end
local sizey = export.size(y)
if sizex ~= sizey then
return false
end
end
end
end
sizex = sizex + 1
return true
end
end
local sizey = export.size(y)
return x == y
if sizex ~= sizey then
return false
end
return true
end
end
return x == y
return de(x, y)
end
end


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handle such tables correctly but be less efficient on lists than
handle such tables correctly but be less efficient on lists than
export.deepEqualsList.
export.deepEqualsList.
NOTE: This is *NOT* smart enough to properly handle cycles; in such a case, it
will get into an infinite loop.
]]
]]
function export.deepEqualsList(x, y)
function export.deepEqualsList(x, y)
if type(x) == "table" and type(y) == "table" then
local already_seen = {}
if #x ~= #y then
return false
local function de(x, y)
end  
if type(x) == "table" and type(y) == "table" then
for key, value in ipairs(x) do
if not already_seen[x] then
if not export.deepEqualsList(value, y[key]) then
already_seen[x] = {}
return false
if not already_seen[x][y] then
already_seen[x][y] = true
if #x ~= #y then
return false
end  
for key, value in pairs(x) do
if not de(value, y[key]) then
return false
end
end
end
end
end
return true
end
end
return true
return x == y
end
end
return x == y
return de(x, y)
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. Shallow comparison is used unless `deepCompare` is given
portion of the list. Comparison is by value, using `deepEquals`.
(in which case comparison is done using `deepEqualsList`).
 
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
ignored.
]]
]]
function export.contains(list, x, deepCompare)
function export.contains(list, x)
checkType('contains', 1, list, 'table')
checkType('contains', 1, list, 'table')
if deepCompare then
for _, v in ipairs(list) do
for _, v in ipairs(list) do
if export.deepEquals(v, x) then return true end
if export.deepEqualsList(v, x) then return true end
end
else
for _, v in ipairs(list) do
if v == x then return true end
end
end
end
return false
return false
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--[[
--[[
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. Shallow comparison is used
either the array or hashmap portion of the table. Comparison is by value, using
unless `deepCompare` is given (in which case comparison is done using
`deepEquals`.
`deepEquals`).
 
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
ignored.
]]
]]
function export.tableContains(tbl, x, deepCompare)
function export.tableContains(tbl, x)
checkType('tableContains', 1, tbl, 'table')
checkType('tableContains', 1, tbl, 'table')
if deepCompare then
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
end
else
for _, v in pairs(tbl) do
if v == x then return true end
end
end
end
return false
return false
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--[[
--[[
Given a list and a value to be inserted, append or insert the value if not
Given a list and a value to be inserted, append or insert the value if not
already present in the list. Shallow comparison is used unless `deepCompare`
already present in the list. Comparison is by value, using `deepEquals`.
is given (in which case comparison is done using `deepEqualsList`). Appends to
Appends to the end, like the default behavior of table.insert(), unless `pos`
the end, like the default behavior of table.insert(), unless `pos` is given,
is given, in which case insertion happens at position `pos` (i.e. before the
in which case insertion happens at position `pos` (i.e. before the existing
existing item at position `pos`).
item at position `pos`).


NOTE: The order of `item` and `pos` is reversed in comparison to table.insert(),
NOTE: The order of `item` and `pos` is reversed in comparison to table.insert(),
which uses `table.insert(list, item)` to insert at the end but
which uses `table.insert(list, item)` to insert at the end but
`table.insert(list, pos, item)` to insert at position POS.
`table.insert(list, pos, item)` to insert at position POS.
NOTE: This used to do shallow comparison by default and accepted a fourth
'deepCompare' param to do deep comparison. This param is still accepted but now
ignored.
]]
]]
-- append to list if element not already present
function export.insertIfNot(list, item, pos)
function export.insertIfNot(list, item, pos, deepCompare)
if not export.contains(list, item) then
if not export.contains(list, item, deepCompare) then
if pos then
if pos then
table.insert(list, pos, item)
table.insert(list, pos, item)
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end
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)
i = (i and i < 0 and #list - i + 1) or i or (s and s < 0 and #list) or 1
j = (j and j < 0 and #list - j + 1) or j or (s and s < 0 and 1) or #list
s = s or (j < i and -1) or 1
if (
i == 0 or i % 1 ~= 0 or
j == 0 or j % 1 ~= 0 or
s == 0 or s % 1 ~= 0
) then
error("Arguments i, j and s must be non-zero integers.")
end
return i, j, s
end
function export.reduce(list, func, i, j, s)
i, j, s = getIteratorValues(i, j , s, list)
local ret = list[i]
for k = i + s, j, s do
ret = func(ret, k, list[k])
end
return ret
end
function export.apply(list, func, i, j, s)
local modified_list = export.deepcopy(list)
i, j, s = getIteratorValues(i, j , s, modified_list)
for k = i, j, s do
modified_list[k] = func(k, modified_list[k])
end
return modified_list
end
function export.all(list, func, i, j, s)
i, j, s = getIteratorValues(i, j , s, list)
local ret = true
for k = i, j, s do
ret = ret and not not (func(k, list[k]))
if not ret then break end
end
return ret
end
function export.any(list, func, i, j, s)
i, j, s = getIteratorValues(i, j , s, list)
local ret = false
for k = i, j, s do
ret = ret or not not (func(k, list[k]))
if ret then break end
end
return ret
end
end


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Conjunction to use; defaults to "and".
Conjunction to use; defaults to "and".
- italicizeConj
- italicizeConj
Italicize conjunction: for [[Module:Template:also]]
Italicize conjunction: for [[Module:also]]
- dontTag
- dontTag
Don't tag the serial comma and serial "and". For error messages, in
Don't tag the serial comma and serial "and". For error messages, in
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end
end
return true
return true
end
--[[
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)
for _, alias in pairs(aliases) do
t[alias] = t[k]
end
end
end


return export
return export
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