The wiki has moved!

Visit the new wiki at stationeers-wiki.com The old wiki here at legacy.stationeers-wiki.com will sunset eventually.

Edits made after the 7th of March 6PM EST were NOT carried over to the new server as previously announced right here in this box.

 Actions

Module

Difference between revisions of "TableTools"

From Unofficial Stationeers Wiki

(start module with useful tools for dealing with Lua tables)
 
m (41 revisions imported)
 
(42 intermediate revisions by 3 users not shown)
Line 1: Line 1:
−
-- This module includes a number of functions that can be useful when dealing with Lua tables.
+
--[[
 +
------------------------------------------------------------------------------------
 +
--                              TableTools                                      --
 +
--                                                                                --
 +
-- This module includes a number of functions for dealing with Lua tables.       --
 +
-- It is a meta-module, meant to be called from other Lua modules, and should    --
 +
-- not be called directly from #invoke.                                          --
 +
------------------------------------------------------------------------------------
 +
--]]
 +
 
 +
local libraryUtil = require('libraryUtil')
  
 
local p = {}
 
local p = {}
Line 6: Line 16:
 
local floor = math.floor
 
local floor = math.floor
 
local infinity = math.huge
 
local infinity = math.huge
 +
local checkType = libraryUtil.checkType
  
 
--[[
 
--[[
−
-----------------------------------------------------------------------------------
+
------------------------------------------------------------------------------------
−
-- Helper functions
+
-- isPositiveInteger
−
-----------------------------------------------------------------------------------
+
--
 +
-- This function returns true if the given value is a positive integer, and false
 +
-- if not. Although it doesn't operate on tables, it is included here as it is
 +
-- useful for determining whether a given table key is in the array part or the
 +
-- hash part of a table.
 +
------------------------------------------------------------------------------------
 
--]]
 
--]]
 +
function p.isPositiveInteger(v)
 +
if type(v) == 'number' and v >= 1 and floor(v) == v and v < infinity then
 +
return true
 +
else
 +
return false
 +
end
 +
end
  
−
local function isPositiveInteger(num)
+
--[[
−
-- Returns true if the given number is a positive integer, and false if not.
+
------------------------------------------------------------------------------------
−
if type(num) == 'number' and num >= 1 and floor(num) == num and num < infinity then
+
-- isNan
 +
--
 +
-- This function returns true if the given number is a NaN value, and false
 +
-- if not. Although it doesn't operate on tables, it is included here as it is
 +
-- useful for determining whether a value can be a valid table key. Lua will
 +
-- generate an error if a NaN is used as a table key.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.isNan(v)
 +
if type(v) == 'number' and tostring(v) == '-nan' then
 
return true
 
return true
 
else
 
else
Line 23: Line 55:
  
 
--[[
 
--[[
−
-----------------------------------------------------------------------------------
+
------------------------------------------------------------------------------------
−
-- compressSparseArray
+
-- shallowClone
 +
--
 +
-- This returns a clone of a table. The value returned is a new table, but all
 +
-- subtables and functions are shared. Metamethods are respected, but the returned
 +
-- table will have no metatable of its own.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.shallowClone(t)
 +
local ret = {}
 +
for k, v in pairs(t) do
 +
ret[k] = v
 +
end
 +
return ret
 +
end
 +
 
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- removeDuplicates
 +
--
 +
-- This removes duplicate values from an array. Non-positive-integer keys are
 +
-- ignored. The earliest value is kept, and all subsequent duplicate values are
 +
-- removed, but otherwise the array order is unchanged.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.removeDuplicates(t)
 +
checkType('removeDuplicates', 1, t, 'table')
 +
local isNan = p.isNan
 +
local ret, exists = {}, {}
 +
for i, v in ipairs(t) do
 +
if isNan(v) then
 +
-- NaNs can't be table keys, and they are also unique, so we don't need to check existence.
 +
ret[#ret + 1] = v
 +
else
 +
if not exists[v] then
 +
ret[#ret + 1] = v
 +
exists[v] = true
 +
end
 +
end
 +
end
 +
return ret
 +
end
 +
 
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- numKeys
 
--
 
--
−
-- This takes an array with one or more nil values, and removes the nil values
+
-- This takes a table and returns an array containing the numbers of any numerical
−
-- while preserving the order, so that the array can be safely traversed with
+
-- keys that have non-nil values, sorted in numerical order.
−
-- ipairs.
+
------------------------------------------------------------------------------------
−
-----------------------------------------------------------------------------------
 
 
--]]
 
--]]
−
function p.compressSparseArray(t)
+
function p.numKeys(t)
−
local nums, ret = {}, {}
+
checkType('numKeys', 1, t, 'table')
 +
local isPositiveInteger = p.isPositiveInteger
 +
local nums = {}
 
for k, v in pairs(t) do
 
for k, v in pairs(t) do
 
if isPositiveInteger(k) then
 
if isPositiveInteger(k) then
Line 39: Line 116:
 
end
 
end
 
table.sort(nums)
 
table.sort(nums)
 +
return nums
 +
end
 +
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- affixNums
 +
--
 +
-- This takes a table and returns an array containing the numbers of keys with the
 +
-- specified prefix and suffix. For example, for the table
 +
-- {a1 = 'foo', a3 = 'bar', a6 = 'baz'} and the prefix "a", affixNums will
 +
-- return {1, 3, 6}.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.affixNums(t, prefix, suffix)
 +
checkType('affixNums', 1, t, 'table')
 +
checkType('affixNums', 2, prefix, 'string', true)
 +
checkType('affixNums', 3, suffix, 'string', true)
 +
 +
local function cleanPattern(s)
 +
-- Cleans a pattern so that the magic characters ()%.[]*+-?^$ are interpreted literally.
 +
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 = {}
 +
for k, v in pairs(t) do
 +
if type(k) == 'string' then
 +
local num = mw.ustring.match(k, pattern)
 +
if num then
 +
nums[#nums + 1] = tonumber(num)
 +
end
 +
end
 +
end
 +
table.sort(nums)
 +
return nums
 +
end
 +
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- numData
 +
--
 +
-- Given a table with keys like ("foo1", "bar1", "foo2", "baz2"), returns a table
 +
-- of subtables in the format
 +
-- { [1] = {foo = 'text', bar = 'text'}, [2] = {foo = 'text', baz = 'text'} }
 +
-- Keys that don't end with an integer are stored in a subtable named "other".
 +
-- The compress option compresses the table so that it can be iterated over with
 +
-- ipairs.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.numData(t, compress)
 +
checkType('numData', 1, t, 'table')
 +
checkType('numData', 2, compress, 'boolean', true)
 +
local ret = {}
 +
for k, v in pairs(t) do
 +
local prefix, num = mw.ustring.match(tostring(k), '^([^0-9]*)([1-9][0-9]*)$')
 +
if num then
 +
num = tonumber(num)
 +
local subtable = ret[num] or {}
 +
if prefix == '' then
 +
-- Positional parameters match the blank string; put them at the start of the subtable instead.
 +
prefix = 1
 +
end
 +
subtable[prefix] = v
 +
ret[num] = subtable
 +
else
 +
local subtable = ret.other or {}
 +
subtable[k] = v
 +
ret.other = subtable
 +
end
 +
end
 +
if compress then
 +
local other = ret.other
 +
ret = p.compressSparseArray(ret)
 +
ret.other = other
 +
end
 +
return ret
 +
end
 +
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- compressSparseArray
 +
--
 +
-- This takes an array with one or more nil values, and removes the nil values
 +
-- while preserving the order, so that the array can be safely traversed with
 +
-- ipairs.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.compressSparseArray(t)
 +
checkType('compressSparseArray', 1, t, 'table')
 +
local ret = {}
 +
local nums = p.numKeys(t)
 
for _, num in ipairs(nums) do
 
for _, num in ipairs(nums) do
 
ret[#ret + 1] = t[num]
 
ret[#ret + 1] = t[num]
 
end
 
end
 
return ret
 
return ret
 +
end
 +
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- sparseIpairs
 +
--
 +
-- This is an iterator for sparse arrays. It can be used like ipairs, but can
 +
-- handle nil values.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.sparseIpairs(t)
 +
checkType('sparseIpairs', 1, t, 'table')
 +
local nums = p.numKeys(t)
 +
local i = 0
 +
local lim = #nums
 +
return function ()
 +
i = i + 1
 +
if i <= lim then
 +
local key = nums[i]
 +
return key, t[key]
 +
else
 +
return nil, nil
 +
end
 +
end
 +
end
 +
 +
--[[
 +
------------------------------------------------------------------------------------
 +
-- size
 +
--
 +
-- This returns the size of a key/value pair table. It will also work on arrays,
 +
-- but for arrays it is more efficient to use the # operator.
 +
------------------------------------------------------------------------------------
 +
--]]
 +
function p.size(t)
 +
checkType('size', 1, t, 'table')
 +
local i = 0
 +
for k in pairs(t) do
 +
i = i + 1
 +
end
 +
return i
 
end
 
end
  
 
return p
 
return p

Latest revision as of 15:04, 14 July 2018

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

--[[
------------------------------------------------------------------------------------
--                               TableTools                                       --
--                                                                                --
-- This module includes a number of functions for dealing with Lua tables.        --
-- It is a meta-module, meant to be called from other Lua modules, and should     --
-- not be called directly from #invoke.                                           --
------------------------------------------------------------------------------------
--]]

local libraryUtil = require('libraryUtil')

local p = {}

-- Define often-used variables and functions.
local floor = math.floor
local infinity = math.huge
local checkType = libraryUtil.checkType

--[[
------------------------------------------------------------------------------------
-- isPositiveInteger
--
-- This function returns true if the given value is a positive integer, and false
-- if not. Although it doesn't operate on tables, it is included here as it is
-- useful for determining whether a given table key is in the array part or the
-- hash part of a table.
------------------------------------------------------------------------------------
--]]
function p.isPositiveInteger(v)
	if type(v) == 'number' and v >= 1 and floor(v) == v and v < infinity then
		return true
	else
		return false
	end
end

--[[
------------------------------------------------------------------------------------
-- isNan
--
-- This function returns true if the given number is a NaN value, and false
-- if not. Although it doesn't operate on tables, it is included here as it is
-- useful for determining whether a value can be a valid table key. Lua will
-- generate an error if a NaN is used as a table key.
------------------------------------------------------------------------------------
--]]
function p.isNan(v)
	if type(v) == 'number' and tostring(v) == '-nan' then
		return true
	else
		return false
	end
end

--[[
------------------------------------------------------------------------------------
-- shallowClone
--
-- This returns a clone of a table. The value returned is a new table, but all
-- subtables and functions are shared. Metamethods are respected, but the returned
-- table will have no metatable of its own.
------------------------------------------------------------------------------------
--]]
function p.shallowClone(t)
	local ret = {}
	for k, v in pairs(t) do
		ret[k] = v
	end
	return ret
end

--[[
------------------------------------------------------------------------------------
-- removeDuplicates
--
-- This removes duplicate values from an array. Non-positive-integer keys are
-- ignored. The earliest value is kept, and all subsequent duplicate values are
-- removed, but otherwise the array order is unchanged.
------------------------------------------------------------------------------------
--]]
function p.removeDuplicates(t)
	checkType('removeDuplicates', 1, t, 'table')
	local isNan = p.isNan
	local ret, exists = {}, {}
	for i, v in ipairs(t) do
		if isNan(v) then
			-- NaNs can't be table keys, and they are also unique, so we don't need to check existence.
			ret[#ret + 1] = v
		else
			if not exists[v] then
				ret[#ret + 1] = v
				exists[v] = true
			end
		end	
	end
	return ret
end			

--[[
------------------------------------------------------------------------------------
-- numKeys
--
-- This takes a table and returns an array containing the numbers of any numerical
-- keys that have non-nil values, sorted in numerical order.
------------------------------------------------------------------------------------
--]]
function p.numKeys(t)
	checkType('numKeys', 1, t, 'table')
	local isPositiveInteger = p.isPositiveInteger
	local nums = {}
	for k, v in pairs(t) do
		if isPositiveInteger(k) then
			nums[#nums + 1] = k
		end
	end
	table.sort(nums)
	return nums
end

--[[
------------------------------------------------------------------------------------
-- affixNums
--
-- This takes a table and returns an array containing the numbers of keys with the
-- specified prefix and suffix. For example, for the table
-- {a1 = 'foo', a3 = 'bar', a6 = 'baz'} and the prefix "a", affixNums will
-- return {1, 3, 6}.
------------------------------------------------------------------------------------
--]]
function p.affixNums(t, prefix, suffix)
	checkType('affixNums', 1, t, 'table')
	checkType('affixNums', 2, prefix, 'string', true)
	checkType('affixNums', 3, suffix, 'string', true)

	local function cleanPattern(s)
		-- Cleans a pattern so that the magic characters ()%.[]*+-?^$ are interpreted literally.
		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 = {}
	for k, v in pairs(t) do
		if type(k) == 'string' then			
			local num = mw.ustring.match(k, pattern)
			if num then
				nums[#nums + 1] = tonumber(num)
			end
		end
	end
	table.sort(nums)
	return nums
end

--[[
------------------------------------------------------------------------------------
-- numData
--
-- Given a table with keys like ("foo1", "bar1", "foo2", "baz2"), returns a table
-- of subtables in the format 
-- { [1] = {foo = 'text', bar = 'text'}, [2] = {foo = 'text', baz = 'text'} }
-- Keys that don't end with an integer are stored in a subtable named "other".
-- The compress option compresses the table so that it can be iterated over with
-- ipairs.
------------------------------------------------------------------------------------
--]]
function p.numData(t, compress)
	checkType('numData', 1, t, 'table')
	checkType('numData', 2, compress, 'boolean', true)
	local ret = {}
	for k, v in pairs(t) do
		local prefix, num = mw.ustring.match(tostring(k), '^([^0-9]*)([1-9][0-9]*)$')
		if num then
			num = tonumber(num)
			local subtable = ret[num] or {}
			if prefix == '' then
				-- Positional parameters match the blank string; put them at the start of the subtable instead.
				prefix = 1
			end
			subtable[prefix] = v
			ret[num] = subtable
		else
			local subtable = ret.other or {}
			subtable[k] = v
			ret.other = subtable
		end
	end
	if compress then
		local other = ret.other
		ret = p.compressSparseArray(ret)
		ret.other = other
	end
	return ret
end

--[[
------------------------------------------------------------------------------------
-- compressSparseArray
--
-- This takes an array with one or more nil values, and removes the nil values
-- while preserving the order, so that the array can be safely traversed with
-- ipairs.
------------------------------------------------------------------------------------
--]]
function p.compressSparseArray(t)
	checkType('compressSparseArray', 1, t, 'table')
	local ret = {}
	local nums = p.numKeys(t)
	for _, num in ipairs(nums) do
		ret[#ret + 1] = t[num]
	end
	return ret
end

--[[
------------------------------------------------------------------------------------
-- sparseIpairs
--
-- This is an iterator for sparse arrays. It can be used like ipairs, but can
-- handle nil values.
------------------------------------------------------------------------------------
--]]
function p.sparseIpairs(t)
	checkType('sparseIpairs', 1, t, 'table')
	local nums = p.numKeys(t)
	local i = 0
	local lim = #nums
	return function ()
		i = i + 1
		if i <= lim then
			local key = nums[i]
			return key, t[key]
		else
			return nil, nil
		end
	end
end

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

return p
Retrieved from "https://legacy.stationeers-wiki.com/index.php?title=Module:TableTools&oldid=5764"