Lua function for format string by replaces %1, %2 and so on in the passed string of the passed arguments.

string.format.lua

---Replaces %1, %2 and so on in the passed string of the passed arguments.
---@param str string # The string pattern contains %1 to %9.
---@param ... any # Any types will be passed to tostring.
---@return string str # New formated replaced string.
---@return integer count # Number of operations.
local stringformat = function(str, ...)
	local tostring, select, gsub, t = tostring, select, string.gsub, {}
	for i = 1, select('#', ...) do
		t[tostring(i)] = tostring(select(i, ...))
	end
	return gsub(str, "%%([%d]+)", t)
end

---
---Examples
---

local s = [[%1 says to %2, that %2 did't pay $%3 to %4 for nothing.]]
local t = setmetatable({
	name = 'Aura'
}, {
	__tostring = function(t)
		return tostring(t.name)
	end
})
local a = {
	'Serra',
	'Terra',
	69,
	-- special case where table passed to tostring
	t,
	-- get ignored
	'this get thrown away'
}
local x = stringformat(s, unpack(a))
print(x)

local y = stringformat([[$%3 is $%3.]], unpack(a))
print(y)

local z = stringformat('$%1 is $%1.', 50)
print(z)