added simple Lua interpreter with sample init file, plus useful import module

Author: stevedonovan

assets/import.lua

@@ -0,0 +1,134 @@
+local packages = {}
+local append = table.insert
+local new = luajava.new
+
+-- SciTE requires this, if you want to see stdout immediately...
+
+io.stdout:setvbuf 'no'
+io.stderr:setvbuf 'no'
+
+local function new_tostring (o)
+   return o:toString()
+end
+
+local function call (t,...)
+    local obj,stat
+    if select('#',...) == 1 and type(select(1,...))=='table' then
+        obj = make_array(t,select(1,...))
+    else
+        stat,obj = pcall(new,t,...)
+        if not stat then
+            print(debug.traceback())
+            os.exit(1)
+        end
+    end
+	getmetatable(obj).__tostring = new_tostring
+	return obj
+end
+
+local function import_class (classname,packagename)
+    local res,class = pcall(luajava.bindClass,packagename)
+    if res then
+        _G[classname] = class
+        local mt = getmetatable(class)
+        mt.__call = call
+        return class
+    end
+end
+
+local function massage_classname (classname)
+    if classname:find('_') then
+        classname = classname:gsub('_','$')
+    end
+    return classname
+end
+
+local globalMT = {
+	__index = function(T,classname)
+            classname = massage_classname(classname)
+			for i,p in ipairs(packages) do
+                local class = import_class(classname,p..classname)
+                if class then return class end
+			end
+            print("import cannot find "..classname)
+	end
+}
+setmetatable(_G, globalMT)
+
+function import (package)
+    local i = package:find('%.%*$')
+    if i then -- a wildcard; put into the package list, including the final '.'
+        append(packages,package:sub(1,i))
+    else
+        local classname = package:match('([%w_]+)$')
+        if not import_class(classname,package) then
+            error("cannot find "..package)
+        end
+    end
+end
+
+append(packages,'')
+
+function proxy (classname,obj)
+    classname = massage_classname(classname)
+	-- if the classname contains dots it's assumed to be fully qualified
+	if classname:find('.',1,true) then
+		return luajava.createProxy(classname,obj)
+	end
+	-- otherwise, it must lie on the package path!
+	for i,p in ipairs(packages) do
+		local ok,res = pcall(luajava.createProxy,p..classname, obj)
+		if ok then return res end
+	end
+	error ("cannot find "..classname)
+end
+
+
+function enum(e)
+   --local e = o:GetEnumerator()
+   return function()
+      if e:hasMoreElements() then
+        return e:nextElement()
+     end
+   end
+end
+
+function dump (t)
+    for k,v in pairs(t) do
+        print(k,v)
+    end
+end
+
+function p (o)
+    if type(o) == 'userdata' then
+		local mt = getmetatable(o)
+		if not mt.__tostring then
+			return print('java:'..o:toString())
+		end
+	end
+	print(type(o)..':'..tostring(o))
+end
+
+import 'java.lang.reflect.Array'
+
+function make_array (Type,list)
+    local len
+    local init = type(list)=='table'
+    if init then
+        len = #list
+    else
+        len = list
+    end
+    local arr = Array:newInstance(Type,len)
+    if init then
+        for i,v in ipairs(list) do
+            Array:set(arr,i-1,v)
+        end
+    end
+    return arr
+end
+
+
+import 'java.lang.*'
+import 'java.util.*'
+

init.lua

@@ -0,0 +1,2 @@
+require 'import'
+context = activity:getApplicationContext()

interp.lua

@@ -0,0 +1,58 @@
+require 'socket'
+local c = socket.connect('localhost',3333)
+local log = io.open('log.txt','a')
+
+function readfile(file)
+  local f,err = io.open(file)
+  if not f then return nil,err end
+  local contents = f:read '*a':gsub('\n','\001')
+  f:close()
+  return contents
+end
+
+function eval(line)
+  c:send(line..'\n')
+  local res = c:receive()
+  return res:gsub('\001','\n')
+end
+
+local init,err = readfile 'init.lua'
+if init then
+  print 'loading init.lua'
+  io.write(eval(init)..'\n')
+end
+
+io.write '> '
+local line = io.read()
+
+while line do
+  log:write(line,'\n')
+  local cmd,file = line:match '^%.(.)%s+(.+)$'
+  if file then
+    local mod
+    if cmd == 'm' then
+      mod = file
+      file = mod:gsub('%.','/')..'.lua'
+    end
+    line,err = readfile(file)
+    if mod and line then
+      line = '--mod:'..mod..'\001'..line
+    end
+  else
+    local expr = line:match '^%s*=%s*(.+)$'
+    if expr then
+      line = 'print('..expr..')'
+    end
+  end
+  if line then
+    local res = eval(line)
+    log:write(res,'\n')
+    io.write(res)
+  else
+    print(err)
+  end
+  io.write '> '
+  line = io.read()
+end
+log:close()
+c:close()