Intllib interface upgrade

init.lua

@@ -1,12 +1,14 @@
 local inbox = {}
 
 -- Boilerplate to support localized strings if intllib mod is installed.
-local S
-if intllib then
-  S = intllib.Getter()
-else
-  S = function(s) return s end
-end
+local MP = minetest.get_modpath(
+    minetest.get_current_modname(
+    )
+)
+
+local S, NS = dofile(
+    MP .. "/intllib.lua"
+)
 
 --[[
 TODO

intllib.lua

@@ -0,0 +1,45 @@
+
+-- Fallback functions for when `intllib` is not installed.
+-- Code released under Unlicense <http://unlicense.org>.
+
+-- Get the latest version of this file at:
+--   https://raw.githubusercontent.com/minetest-mods/intllib/master/lib/intllib.lua
+
+local function format(str, ...)
+	local args = { ... }
+	local function repl(escape, open, num, close)
+		if escape == "" then
+			local replacement = tostring(args[tonumber(num)])
+			if open == "" then
+				replacement = replacement..close
+			end
+			return replacement
+		else
+			return "@"..open..num..close
+		end
+	end
+	return (str:gsub("(@?)@(%(?)(%d+)(%)?)", repl))
+end
+
+local gettext, ngettext
+if minetest.get_modpath("intllib") then
+	if intllib.make_gettext_pair then
+		-- New method using gettext.
+		gettext, ngettext = intllib.make_gettext_pair()
+	else
+		-- Old method using text files.
+		gettext = intllib.Getter()
+	end
+end
+
+-- Fill in missing functions.
+
+gettext = gettext or function(msgid, ...)
+	return format(msgid, ...)
+end
+
+ngettext = ngettext or function(msgid, msgid_plural, n, ...)
+	return format(n==1 and msgid or msgid_plural, ...)
+end
+
+return gettext, ngettext