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
                local res = setmetatable({}, getmetatable(lhs) or getmetatable(rhs))
                for i = 1, #lhs do
                        res[i] = lhs[i]
                end
                local l = #lhs
                for i = 1, #rhs do
                        res[i + l] = rhs[i]
                end
                return res
        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, string.format('Tables are not equal length (lhs=%d, rhs=%d)', #lhs, #rhs))
                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.clean(array)
        checkType('Module:Array.clean', 1, array, 'table')
        for i = 1, #array do
                if type(array[i]) == 'table' then
                        arr.clean(array[i])
                end
        end
        setmetatable(array, nil)
        return array
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.diff(array, order)
        checkType('Module:Array.diff', 1, array, 'table')
        checkType('Module:Array.diff', 2, order, 'number', true)
        local res = setmetatable({}, getmetatable(array))
        for i = 1, #array - 1 do
                res[i] = array[i+1] - array[i]
        end
        if order and order > 1 then
                return arr.diff(res, order - 1)
        end
        return res
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.int(array, start, stop)
        checkType('Module:Array.int', 1, array, 'table')
        checkType('Module:Array.int', 2, start, 'number', true)
        checkType('Module:Array.int', 3, stop, 'number', true)
        local res = setmetatable({}, getmetatable(array))
        start = start or 1
        stop = stop or #array
        res[1] = array[start]
        for i = 1, stop - start do
                res[i+1] = res[i] + array[start + i]
        end
        return res
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(array, val, index, unpackVal)
        checkType('Module:Array.insert', 1, array, 'table')
        checkType('Module:Array.insert', 3, index, 'number', true)
        checkType('Module:Array.insert', 4, unpackVal, 'boolean', true)
        local len = #array
        index = index or (len + 1)

        if type(val) == 'table' and unpackVal ~= false then
                local len2 = #val
                for i = 0, len - index do
                        array[len + len2 - i] = array[len - i]
                end
                for i = 0, len2 - 1 do
                        array[index + i] = val[i + 1]
                end
        else
                table.insert(array, index, val)
        end

        return array
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)
        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
        if start < 0 and finish == nil then
                finish = #array + start
                start = 1
        elseif start < 0 then
                start = #array + start
        end
        if finish < 0 then
                finish = #array + finish
        end
        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>