Module:Array

Documentation for this module may be created at Module:Array/doc

-- <nowiki> awawa
local libraryUtil = require('libraryUtil')
local checkType = libraryUtil.checkType
local checkTypeMulti = libraryUtil.checkTypeMulti
local arr = {}

setmetatable(arr, {
	__call = function (_, array)
		return arr.new(array)
	end
})

function arr.__index(t, k)
	if type(k) == 'table' then
		local res = arr.new()
		for i = 1, #t do
			res[i] = t[k[i]]
		end
		return res
	else
		return arr[k]
	end
end

function arr.__tostring(array)
	local dumpObject = require('Module:Logger').dumpObject
	setmetatable(array, nil)
	local str = dumpObject(array, {clean=true, collapseLimit=100})
	setmetatable(array, arr)
	return str
end

function arr.__concat(lhs, rhs)
	if type(lhs) == 'table' and type(rhs) == 'table' then
		return arr.insert(lhs, rhs)
	else
		return tostring(lhs) .. tostring(rhs)
	end
end

function arr.__unm(array)
	return arr.map(array, function(x) return -x end)
end

local function mathTemplate(lhs, rhs, funName, fun)
	checkTypeMulti('Module:Array.' .. funName, 1, lhs, {'number', 'table'})
	checkTypeMulti('Module:Array.' .. funName, 2, rhs, {'number', 'table'})
	local res = setmetatable({}, getmetatable(lhs) or getmetatable(rhs))

	if type(lhs) == 'number' then
		for i = 1, #rhs do
			res[i] = fun(lhs, rhs[i])
		end
	elseif type(rhs) == 'number' then
		for i = 1, #lhs do
			res[i] = fun(lhs[i], rhs)
		end
	else
		assert(#lhs == #rhs, 'Tables are not equal length')
		for i = 1, #lhs do
			res[i] = fun(lhs[i], rhs[i])
		end
	end

	return res
end

function arr.__add(lhs, rhs)
	return mathTemplate(lhs, rhs, '__add', function(x, y) return x + y end)
end

function arr.__sub(lhs, rhs)
	return mathTemplate(lhs, rhs, '__sub', function(x, y) return x - y end)
end

function arr.__mul(lhs, rhs)
	return mathTemplate(lhs, rhs, '__mul', function(x, y) return x * y end)
end

function arr.__div(lhs, rhs)
	return mathTemplate(lhs, rhs, '__div', function(x, y) return x / y end)
end

function arr.__pow(lhs, rhs)
	return mathTemplate(lhs, rhs, '__pow', function(x, y) return x ^ y end)
end

function arr.__lt(lhs, rhs)
	for i = 1, math.min(#lhs, #rhs) do
		if lhs[i] >= rhs[i] then
			return false
		end
	end
	return true
end

function arr.__le(lhs, rhs)
	for i = 1, math.min(#lhs, #rhs) do
		if lhs[i] > rhs[i] then
			return false
		end
	end
	return true
end

function arr.__eq(lhs, rhs)
	if #lhs ~= #rhs then
		return false
	end
	for i = 1, #lhs do
		if lhs[i] ~= rhs[i] then
			return false
		end
	end
	return true
end

function arr.all(array, fn)
	checkType('Module:Array.all', 1, array, 'table')
	if fn == nil then fn = function(item) return item end end
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local i = 1
	while array[i] ~= nil do
		if not fn(array[i], i) then
			return false
		end
		i = i + 1
	end
	return true
end

function arr.any(array, fn)
	checkType('Module:Array.any', 1, array, 'table')
	if fn == nil then fn = function(item) return item end end
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local i = 1
	while array[i] ~= nil do
		if fn(array[i], i) then
			return true
		end
		i = i + 1
	end
	return false
end

function arr.contains(array, elem, useElemTableContent)
	checkType('Module:Array.contains', 1, array, 'table')
	if type(elem) == 'table' and useElemTableContent ~= false then
		local elemMap = {}
		local isFound = {}
		arr.each(elem, function(x, i) elemMap[x] = i; isFound[i] = false end)
		for i = 1, #array do
			local j = elemMap[array[i]]
			if j then
				isFound[j] = true
			end
		end
		return arr.all(isFound, true)
	else
		return arr.any(array, function(item) return item == elem end)
	end
end

function arr.count(array, fn)
	checkType('Module:Array.count', 1, array, 'table')
	if fn == nil then fn = function(item) return item end end
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local count = 0
	for i = 1, #array do
		if fn(array[i]) then
			count = count + 1
		end
	end
	return count
end

function arr.each(array, fn)
	checkType('Module:Array.each', 1, array, 'table')
	checkType('Module:Array.each', 2, fn, 'function')
	local i = 1
	while array[i] ~= nil do
		fn(array[i], i)
		i = i + 1
	end
end

function arr.filter(array, fn)
	checkType('Module:Array.filter', 1, array, 'table')
	if fn == nil then fn = function(item) return item end end
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local r = setmetatable({}, getmetatable(array))
	local len = 0
	local i = 1
	while array[i] ~= nil do
		if fn(array[i], i) then
			len = len + 1
			r[len] = array[i]
		end
		i = i + 1
	end
	return r
end

function arr.find(array, fn, default)
	checkType('Module:Array.find', 1, array, 'table')
	checkTypeMulti('Module:Array.find_index', 2, fn, {'function', 'table', 'number', 'boolean'})
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local i = 1
	while array[i] ~= nil do
		if fn(array[i], i) then
			return array[i], i
		end
		i = i + 1
	end
	return default
end

function arr.find_index(array, fn, default)
	checkType('Module:Array.find_index', 1, array, 'table')
	checkTypeMulti('Module:Array.find_index', 2, fn, {'function', 'table', 'number', 'boolean'})
	if type(fn) ~= 'function' then
		local val = fn
		fn = function(item) return item == val end
	end
	local i = 1
	while array[i] ~= nil do
		if fn(array[i], i) then
			return i
		end
		i = i + 1
	end
	return default
end

function arr.newIncrementor(start, step)
	checkType('Module:Array.newIncrementor', 1, start, 'number', true)
	checkType('Module:Array.newIncrementor', 2, step, 'number', true)
	step = step or 1
	local n = (start or 1) - step
	local obj = {}
	return setmetatable(obj, {
		__call = function() n = n + step return n end,
		__tostring = function() return n end,
		__index = function() return n end,
		__newindex = function(self, k, v)
			if k == 'step' and type(v) == 'number' then
				step = v
			elseif type(v) == 'number' then
				n = v
			end
		end,
		__concat = function(x, y) return tostring(x) .. tostring(y) end
	})
end

function arr.intersect(array1, array2)
	checkType('Module:Array.intersect', 1, array1, 'table')
	checkType('Module:Array.intersect', 2, array2, 'table')
	local array2Elements = {}
	local res = setmetatable({}, getmetatable(array1) or getmetatable(array2))
	local len = 0
	arr.each(array2, function(item) array2Elements[item] = true end)
	arr.each(array1, function(item)
		if array2Elements[item] then
			len = len + 1
			res[len] = item
		end
	end)
	return res
end

function arr.intersects(array1, array2)
	checkType('Module:Array.intersects', 1, array1, 'table')
	checkType('Module:Array.intersects', 2, array2, 'table')
	local small = {}
	local large
	if #array1 <= #array2 then
		arr.each(array1, function(item) small[item] = true end)
		large = array2
	else
		arr.each(array2, function(item) small[item] = true end)
		large = array1
	end
	return arr.any(large, function(item) return small[item] end)
end

function arr.insert(array1, array2, index)
	checkType('Module:Array.insert', 1, array1, 'table')
	checkType('Module:Array.insert', 2, array2, 'table')
	checkType('Module:Array.insert', 3, index, 'number', true)
	local len1 = #array1
	local len2 = #array2
	index = index or (len1 + 1)
	local res = setmetatable({}, getmetatable(array1) or getmetatable(array2))

	for i = 1, (len1 + len2) do
		if i < index then
			res[i] = array1[i]
		elseif i < (index + len2) then
			res[i] = array2[i - index + 1]
		else
			res[i] = array1[i - len2]
		end
	end

	return res
end

function arr.map(array, fn)
	checkType('Module:Array.map', 1, array, 'table')
	checkType('Module:Array.map', 2, fn, 'function')
	local len = 0
	local r = setmetatable({}, getmetatable(array))
	local i = 1
	while array[i] ~= nil do
		local tmp = fn(array[i], i)
		if tmp ~= nil then
			len = len + 1
			r[len] = tmp
		end
		i = i + 1
	end
	return r
end

function arr.max_by(array, fn)
	checkType('Module:Array.max_by', 1, array, 'table')
	checkType('Module:Array.max_by', 2, fn, 'function')
	return unpack(arr.reduce(array, function(new, old, i)
		local y = fn(new)
		return y > old[2] and {new, y, i} or old
	end, {nil, -math.huge}))
end

function arr.max(array)
	checkType('Module:Array.max', 1, array, 'table')
	local val, _, i = arr.max_by(array, function(x) return x end)
	return val, i
end

function arr.min(array)
	checkType('Module:Array.min', 1, array, 'table')
	local val, _, i = arr.max_by(array, function(x) return -x end)
	return val, i
end

function arr.new(array)
	array = array or {}
	for _, v in pairs(array) do
		if type(v) == 'table' then
			arr.new(v)
		end
	end

	if getmetatable(array) == nil then
		setmetatable(array, arr)
	end

	return array
end

function arr.range(start, stop, step)
	checkType('Module:Array.range', 1, start, 'number')
	checkType('Module:Array.range', 2, stop, 'number', true)
	checkType('Module:Array.range', 3, step, 'number', true)
	local array = setmetatable({}, arr)
	local len = 0
	if not stop then
		stop = start
		start = 1
	end
	for i = start, stop, step or 1 do
		len = len + 1
		array[len] = i
	end
	return array
end

function arr.reduce(array, fn, accumulator)
	checkType('Module:Array.reduce', 1, array, 'table')
	checkType('Module:Array.reduce', 2, fn, 'function')
	local acc = accumulator
	local i = 1
	if acc == nil then
		acc = array[1]
		i = 2
	end
	while array[i] ~= nil do
		acc = fn(array[i], acc, i)
		i = i + 1
	end
	return acc
end

function arr.reject(array, fn)
	checkType('Module:Array.reject', 1, array, 'table')
	checkTypeMulti('Module:Array.reject', 2, fn, {'function', 'table', 'number', 'boolean'})
	if fn == nil then fn = function(item) return item end end
	if type(fn) ~= 'function' and type(fn) ~= 'table' then
		fn = {fn}
	end
	local r = setmetatable({}, getmetatable(array))
	local len = 0
	if type(fn) == 'function' then
		local i = 1
		while array[i] ~= nil do
			if not fn(array[i], i) then
				len = len + 1
				r[len] = array[i]
			end
			i = i + 1
		end
	else
		local rejectMap = {}
		arr.each(fn, function(item) rejectMap[item] = true end)
		local i = 1
		while array[i] ~= nil do
			if not rejectMap[array[i]] then
				len = len + 1
				r[len] = array[i]
			end
			i = i + 1
		end
	end
	return r
end

function arr.rep(val, n)
	checkTypeMulti('Module:Array.rep', 1, val, {'function', 'table', 'number', 'boolean'})
	checkType('Module:Array.rep', 2, n, 'number')
	local r = setmetatable({}, arr)
	for i = 1, n do
		r[i] = val
	end
	return r
end

function arr.scan(array, fn, accumulator)
	checkType('Module:Array.scan', 1, array, 'table')
	checkType('Module:Array.scan', 2, fn, 'function')
	local acc = accumulator
	local r = setmetatable({}, getmetatable(array))
	local i = 1
	while array[i] ~= nil do
		if i == 1 and not accumulator then
			acc = array[i]
		else
			acc = fn(array[i], acc)
		end
		r[i] = acc
		i = i + 1
	end
	return r
end

function arr.slice(array, start, finish)
	checkType('Module:Array.slice', 1, array, 'table')
	checkType('Module:Array.slice', 2, start, 'number', true)
	checkType('Module:Array.slice', 3, finish, 'number', true)
	start = start or 1
	finish = finish or #array
	local r = setmetatable({}, getmetatable(array))
	local len = 0
	for i = start, finish do
		len = len + 1
		r[len] = array[i]
	end
	return r
end

function arr.split(array, count)
	checkType('Module:Array.split', 1, array, 'table')
	checkType('Module:Array.split', 2, count, 'number')
	local x = setmetatable({}, getmetatable(array))
	local y = setmetatable({}, getmetatable(array))
	for i = 1, #array do
		table.insert(i <= count and x or y, array[i])
	end
	return x, y
end

function arr.sum(array)
	checkType('Module:Array.sum', 1, array, 'table')
	local res = 0
	for i = 1, #array do
		res = res + array[i]
	end
	return res
end

function arr.take(array, count, offset)
	checkType('Module:Array.take', 1, array, 'table')
	checkType('Module:Array.take', 2, count, 'number')
	checkType('Module:Array.take', 3, offset, 'number', true)
	local x = setmetatable({}, getmetatable(array))
	for i = offset or 1, #array do
		if i <= count then
			table.insert(x, array[i])
		end
	end
	return x
end

function arr.take_every(array, n, offset)
	checkType('Module:Array.take_every', 1, array, 'table')
	checkType('Module:Array.take_every', 2, n, 'number')
	checkType('Module:Array.take_every', 3, offset, 'number', true)
	local r = setmetatable({}, getmetatable(array))
	local len = 0
	local i = offset or 1
	while array[i] ~= nil do
		len = len + 1
		r[len] = array[i]
		i = i + n
	end
	return r
end

function arr.unique(array, fn)
	checkType('Module:Array.unique', 1, array, 'table')
	checkType('Module:Array.unique', 2, fn, 'function', true)
	fn = fn or function(item) return item end
	local r = setmetatable({}, getmetatable(array))
	local len = 0
	local hash = {}
	local i = 1
	while array[i] ~= nil do
		local id = fn(array[i])
		if not hash[id] then
			len = len + 1
			r[len] = array[i]
			hash[id] = true
		end
		i = i + 1
	end
	return r
end

function arr.update(array, indexes, values)
	checkType('Module:Array.update', 1, array, 'table')
	checkTypeMulti('Module:Array.update', 2, indexes, {'table', 'number'})
	if type(indexes) == 'number' then
		indexes = {indexes}
	end
	if type(values) == 'table' then
		assert(#indexes == #values, 'Values array must be of equal length as index array')
		for i = 1, #indexes do
			array[indexes[i]] = values[i]
		end
	else
		for i = 1, #indexes do
			array[indexes[i]] = values
		end
	end
	return array
end

function arr.zip(...)
	local arrays = { ... }
	checkType('Module:Array.zip', 1, arrays[1], 'table')
	local r = setmetatable({}, getmetatable(arrays[1]))
	local _, longest = arr.max_by(arrays, function(array) return #array end)
	for i = 1, longest do
		local q = {}
		for j = 1, #arrays do
			table.insert(q, arrays[j][i])
		end
		table.insert(r, q)
	end
	return r
end

return arr
-- </nowiki>