View source for Module:Core

local Utils = {}

-- * Function functions :V

function Utils.id(x)
	return x
end

-- * Collection functions.

function Utils.find(tbl, v_, k_)
	for _, v in pairs(tbl) do
		if k_ and v and v[k_] == v_ or not k_ and v == v_ then
			return v
		end
	end
	return false
end

function Utils.includes(tbl, v_, k_)
	for _, v in pairs(tbl) do
		if k_ and v and v[k_] == v_ or not k_ and v == v_ then
			return true
		end
	end
	return false
end

function Utils.map(tbl, fn)
	local result = {}
	for k, v in pairs(tbl) do
		table.insert(result, fn(v, k))
	end
	return result
end
 
function Utils.filter(tbl, pred)
	local result = {}
	for k, v in pairs(tbl) do
		if pred(v, k) then
			table.insert(result, v)
		end
	end
	return result
end

function Utils.first(tbl)
    for k, v in pairs(tbl) do
        return k, v
    end
end

function Utils.keys(tbl)
	local result = {}
	for k, _ in pairs(tbl) do
		table.insert(result, k)
	end
	return result
end

function Utils.ifind(arr, v_)
	for i, v in ipairs(arr) do
		if v == v_ then
			return i
		end
	end
	return false
end

function Utils.ifindBy(arr, p)
	for i, v in ipairs(arr) do
		if p(v) then
			return v, i
		end
	end
	return false
end

function Utils.imax(arr)
    local maxValue
    local maxIndex
	for i, v in ipairs(arr) do
		if not maxValue or v > maxValue then
			maxValue = v
			maxIndex = i
		end
	end
	return maxValue
end

function Utils.imap(arr, fn)
	local result = {}
	for i, v in ipairs(arr) do
		table.insert(result, fn(v, i))
	end
	return result
end

function Utils.ifilter(arr, pred)
	local result = {}
	for i, v in ipairs(arr) do
		if pred(v, i) then
			table.insert(result, v)
		end
	end
	return result
end

function Utils.ifirst(arr)
    for k, v in ipairs(arr) do
        return k, v
    end
end

function Utils.insertNew(arr, el)
    if not Utils.find(arr, el) then
        table.insert(arr, el)
    end
end

function Utils.concat(arr1, arr2)
    for i = 1, #arr2 do
        arr1[#arr1 + 1] = arr2[i]
    end
    return arr1
end

Utils.join = table.concat

function Utils.ijoin(arr, sep)
    sep = sep or ""
    return table.concat(arr, sep)
end

function Utils.icopy(arr)
    return Utils.imap(arr, function(v) return v end)
end

function Utils.isort(arr)
    local result = Utils.icopy(arr)
    table.sort(result)
    return result
end

function Utils.isum(arr, result)
    result = result or 0
    for _, v in ipairs(arr) do
        result = result + (v or 0)
    end
    return result
end

-- * Number functions.

function Utils.round(x)
    return x % 2 ~= 0.5 and math.floor(x + 0.5) or x - 0.5
end

-- * String functions.

function Utils.pad(s, n, c)
    c = c or " "
    n = n or 0
    s = tostring(s) or ""
    return #s < n and string.rep(c, n - #s) .. s or s
end

function Utils.trim(s)
    return string.gsub(s, "^%s*(.-)%s*$", "%1")
end

function Utils.startsWith(s, ss)
    return string.sub(s, 1, string.len(ss)) == ss
end

-- Capitalize each word in a string.
function Utils.capitalize(s)
    s = s:gsub("(%s)(%l)", function(a, b) return a .. string.upper(b) end)
    s = s:gsub("^(%l)", function(a) return string.upper(a) end)
    return s
end

-- * Wikitext/HTML functions.

function Utils.category(name)
    return "[[" .. "Category:" .. name .. "]]"
end

function Utils.red(s)
    return Utils.format{[[<span style="color:red">${s}</span>]], s = s}
end

-- * Calling arbitrary Lua functions using #invoke.

-- Used to call Formatting:tooltip in Template:Tooltip, mainly because Lua code properly escapes characters,
-- so that span's title attribute always works.
function Utils.method(frame)
	local m = require("Module:" .. frame.args[1])
	local f = frame.args[2]
	local args = {}
	for k, v in ipairs(frame.args) do
		if type(k) == "number" and k >= 3 and type(v) == "string" then
			table.insert(args, v)
		end
	end
	return m[f](m, unpack(args))
end

-- * Frame functions.

local getArgs = require("Module:GetArgs")

-- Unused.
function Utils.getContext(frame)
    local frame1 = frame:getParent()
    if frame1 then
        local frame2 = frame1:getParent()
        if frame2 then
            return { pagename = frame2:getTitle(), args = getArgs{ frame = frame2 } }
        else
            return { pagename = frame1:getTitle(), args = getArgs{ frame = frame1 } }
        end
    else
        return { pagename = frame:getTitle(), args = getArgs{ frame = frame } }
    end
end

-- getParent -> getArgs
function Utils.getParentArgs(frame)
    local frame1 = frame:getParent()
    if frame1 then
        return getArgs{ frame = frame1 }
    else
        return nil
    end
end

-- getArgs + getParent -> getArgs, "implicit" args can be defined in the template (e.g. pagename={{PAGENAME}})
-- "explicit" args are user defined.
function Utils.getTemplateArgs(frame)
    local frame1 = frame:getParent()
    if frame1 then
        return { implicit = getArgs{ frame = frame }, explicit = getArgs{ frame = frame1 } }
    else
        return { implicit = getArgs{ frame = frame }, explicit = {} }
    end
end

function Utils.requireModule(name)
    local success, data = pcall(function () return require(string.format("Module:%s", name)) end)
    -- module without return (or empty, nil, false, true return) gives success = true, data = true
    if data == true then
        return false, nil
    else
        return success, data
    end
end

-- * Testing functions.

function Utils.debugPrint(x, i)
    i = i or 0
    if type(x) == "table" then
        for k, v in pairs(x) do
            mw.log(
                string.rep("  ", i) .. tostring(k) .. " : " .. type(k) .. " = " ..
                (type(v) == "table" and "table" or tostring(v) .. " : " .. type(v))
            )
            if type(v) == "table" then
                Utils.debugPrint(v, i + 1)
            end
        end
    else
        mw.log(tostring(x) .. " : " .. type(x))
    end
end

local function showValue(v)
    return type(v) == "string" and string.format('"%s"', v) or type(v) == "function" and '"function"' or tostring(v)
end

function Utils.js(x, i)
    i = i or 0
    local r = ""
    if type(x) == "table" then
        r = "{\n"
        for k, v in pairs(x) do
            if type(v) == "table" then
                r = r .. string.rep("  ", i + 1) .. tostring(k) .. ": " .. Utils.json(v, i + 1)
            else
                r = r .. string.rep("  ", i + 1) .. tostring(k) .. ": " .. showValue(v) .. ",\n"
            end
        end
        r = r .. string.rep("  ", i) .. (i == 0 and "}\n" or "},\n")
    else
        return showValue(x)
    end
    return r
end

function Utils.registerFormatTests(obj, tests, fn)
    obj.run_format_tests = function()
        for _, test in ipairs(tests) do
            local result = obj.format(nil, test)
            mw.log(fn and fn(result) or result)
        end
    end
end

function Utils.registerTableTests(obj, tests, fn)
    obj.run_table_tests = function()
        for _, test in ipairs(tests) do
            local result = obj:Table(test)
            mw.log(fn and fn(result) or result)
        end
    end
end

function Utils.test(obj, desc, fn)
    obj.test = function()
        mw.log(desc)
        fn(obj)
        mw.log("ok")
    end
end

Utils.log = mw.log

function Utils.format(s, lookup)
	if not lookup then
		lookup = s
		s = lookup[1]
		table.remove(lookup, 1)
	end
	return (string.gsub(s, '${([^%.%!%:%}%[%]]+)%[?([^%.%!%:%}%]]*)%]?%.?([^%!%:%}]*)!?([^%:%}]?):?([^%}]*)}', 
		function(name, element, attribute, conversion, format_spec)
			--local start_of_value, end_of_value, value = string.find(x, '^${(.-)[[.!:}]')
			--local start_of_access, end_of_access, access = string.find(x, '^${.-%[(.-)%][!:}]')
			--if not access then
			--	start_of_access, end_of_access, access = string.find(x, '^${[^:]-%.(.-)[!:}]')
			--end
			--local start_of_conversion, end_of_conversion, conversion = string.find(x, '^${.-!(.)[:}]')
			--local start_of_format_spec, end_of_format_spec, format_spec = string.find(x, ':(.*)}$')

			local value = lookup[name]
			if string.len(element) > 0 then
				value = value[element]
			elseif string.len(attribute) > 0 then
				value = value[attribute]
			end

			if string.len(conversion) > 0 then
				if conversion == 's' then
					value = tostring(value)
				end
			end

			if string.len(format_spec) > 0 then
				local start_of_sign, end_of_sign, sign = string.find(format_spec, '([+%- ])')
				local start_of_width, end_of_width, width, comma, precision, option = string.find(format_spec, '(%d*)(,?)([.0-9]*)([bcdeEfFgGnosxX%%]?)$')
				precision = string.sub(precision, 2)
				local number = tonumber(value)
				if #width > 0 then
					if number then
						value = string.format(string.format(number % 1 ~= 0 and "%%0%s.%sf" or "%%0%sd", width, #precision > 0 and precision or 0), number)
					end
					value = string.format(string.format("%%0%ss", width), value)
				elseif #precision > 0 and number then
					value = string.format(string.format("%%0%s.%sf", width, precision), number)
				end
				if sign then
					if number and number > 0 then
						if sign == "+" then
							value = "+" .. value
						elseif sign == " " then
							value = " " .. value
						end
					end
				end
			end

			return value
		end))
end

function Utils.split(string, separator, max_split, plain)
	assert(separator ~= '')
	assert(max_split == nil or max_split >= 1)

	local default_separator = false

	local result = {}

	if not separator or separator == '' then
		separator = '%s+'
		plain = false
		string = mw.text.trim(string)
		if string == '' then
			return result
		end
	end

	max_split = max_split or -1

	local item_index, start_index = 1, 1
	local separator_start, separator_end = mw.ustring.find(string, separator, start_index, plain)
	while separator_start and max_split ~= 0 do
		result[item_index] = mw.ustring.sub(string, start_index, separator_start - 1)
		item_index = item_index + 1
		start_index = separator_end + 1
		separator_start, separator_end = mw.ustring.find(string, separator, start_index, plain)
		max_split = max_split - 1
	end
	result[item_index] = mw.ustring.sub(string, start_index)

	return result
end

return Utils
Description	What you type	What you get
Italic	''Italic text''	Italic text
Bold	'''Bold text'''	Bold text
Bold & italic	'''''Bold & italic text'''''	*Bold & italic text*