How to localize MUSHclient messages into other languages

-- stuff already localized
locale = "en" -- change to suit you

dofile (locale .. ".lua")

-- make copy
original = { 
    messages = messages, 
    formatted = formatted, 
    times = times, 
    headings = headings 
    }

messages, formatted, times, headings = nil 

-- from distribution
dofile ("Localize_template.lua")

-- make copy
distribution = { 
    messages = messages, 
    formatted = formatted, 
    times = times, 
    headings = headings 
    }

messages, formatted, times, headings = nil 

function compare_table (name)
 local count = 0
 local old = original [name]
 local new = distribution [name]

 print ("Processing table", name)
 print ""

 -- new message is in distribution, but not in already localized file
  for k, v in pairs (new) do
    if not old [k] then
      count = count + 1
      print (string.format ("  New message: %q", k))
    end -- if not there
  end -- for
  
  
  print ("Found ", count, " new messages")  
  print ""

  count = 0
  
 -- old message is in already localized file, but not in distribution
  for k, v in pairs (old) do
    if not new [k] then
      count = count + 1
      print (string.format ("  Deleted message: %q", k))
    end -- if not there
  end -- for
  
  print ("Found ", count, " deleted messages")  
  print ""
  
end -- compare_table

compare_table ("messages")
compare_table ("formatted")
compare_table ("times")
compare_table ("headings")

Processing table	messages

  New message: "You must specify a font file."
  New message: "You must specify some text to insert."
Found 	2	 new messages

Found 	0	 deleted messages

Processing table	formatted

  New message: "Chat sessions for %s"
  New message: "Saturation: %5.3f"
Found 	2	 new messages

Found 	0	 deleted messages

Processing table	times

  New message: "%A, %#d %B %Y, %#I:%M %p"
Found 	1	 new messages

Found 	0	 deleted messages

Processing table	headings

  New message: "When"
Found 	1	 new messages

  Deleted message: "Action"
Found 	1	 deleted messages

In en.lua:  "This is a 2-line\nmessage"

In program output: "This is a 2-line\
message"

CString s = "You need ";
s += atoi (a);
s += " to ";
s += aoi (b);
s += " piece";
if (b != 1)
 s += "s";

CString s = TFormat ("You need %i to %i piece%s", 
                    a, b, b == 1 ? "" : "s");

-- make copy of original tables
orig_messages = messages
orig_formatted = formatted
orig_times = times
orig_headings = headings

-- empty them out so __index is triggered
-- save original tables so we can look them up eventually

messages  = { _orig = orig_messages }
formatted = { _orig = orig_formatted }
times     = { _orig = orig_times }
headings  = { _orig = orig_headings }

counts = {} -- keep counts here

-- metatable for messages, titles, headings
mt_static = {
  -- called to access an entry
  __index=
    function (t, name)
      local s = rawget (t._orig, name)
      if s == nil or #s == 0 then
        counts [name] = (counts [name] or 0) + 1
      end -- not translated yet
      return s
    end;
  }
  
-- metatable for formatted messages
mt_formatted = {
  -- called to access an entry
  __index=
    function (t, name)
      local f = rawget (t._orig, name)
      -- no function? not translated then
      if f == nil then
        counts [name] = (counts [name] or 0) + 1
        return nil
      end
      assert (type (f) == "function")
    
      -- return a function, that will count if the original function
      -- returns an empty string
      return function (...)
         local s = f (...)  -- call original function
         if type (s) ~= "string" or #s == 0 then
           counts [name] = (counts [name] or 0) + 1
         end -- not translated
         return s  -- return translated value
         end -- function 
     end;
  }
  
-- apply the metatables
setmetatable (messages,   mt_static)
setmetatable (times,      mt_static)
setmetatable (headings,   mt_static)
setmetatable (formatted,  mt_formatted)

-- the user will call world.TranslateDebug to invoke this
function Debug ()
   
  -- for sorting
  local t = {}
  
  -- build into table which can be sorted
  for k, v in pairs (counts) do
    table.insert (t, k)
  end -- for

  -- clear out notepad, make heading
  utils.appendtonotepad ("translation", "Translation counts\n\n", true)

  -- sort into descending order
  table.sort (t, function (a, b)
                  return counts [a] > counts [b]
                 end)
                    
  -- display results
  for k, v in ipairs (t) do
    utils.appendtonotepad ("translation", string.format ("%4i: %q \n", counts [v], v))
  end -- for
  
end -- Debug

Translation counts

  12: "Ready" 
   2: "Alias: %s" 
   2: "Clipboard converted for use with the Forum, %i change%s made" 
   2: "&Flip To World	Ctrl+Alt+Space" 
   2: "&Send To World	Shift+Ctrl+S" 
   2: "The connection to %s is not open. Attempt to reconnect?" 
   2: "Connecting to %s, port %d" 
   2: "--- Connected on %A, %B %d, %Y, %#I:%M %p ---" 
   1: "Trigger: %s" 
   1: "For information and assistance about MUSHclient visit our forum at:" 
   1: "Go to forum" 
   1: "Execution of line %i column %i" 
   1: "--- Disconnected on %A, %B %d, %Y, %#I:%M %p ---" 
   1: "Opening world \"%s\"" 
   1: "World: %s" 
   1: "No active world" 
   1: "Script error" 
   1: "--- Connected for %i day%s, %i hour%s, %i minute%s, %i second%s. ---" 
   1: "The \"%s\" server has closed the connection" 
   1: "Immediate execution" 
   1: "Written by Nick Gammon."