module list load module implicit using metatables

git-svn-id: https://svn.spreadspace.org/gcsd/trunk@31 ac14a137-c7f1-4531-abe0-07747231d213

1 files changed, 19 insertions, 16 deletions

diff --git a/src/module_list.lua b/src/module_list.lua
index 990fe5a..b42f2ec 100644
--- a/src/module_list.lua
+++ b/src/module_list.lua
@@ -35,6 +35,23 @@ local defines = require("defines")
 module_list = {}
 
 module_list.classes = {}
+local mt = {}
+function mt.__index(table, key)
+   local old_path = package.path
+   package.path = "./modules/?.lua"
+   
+   local value = rawget(table, key)
+   if(value ~= nil) then return value end
+   
+   log.printf(log.DEBUG, "load module class: %s", key)
+   value = require(key)
+   rawset(table, key, value)
+   
+   package.path = old_path
+   return value
+end
+setmetatable(module_list.classes, mt)
+
 module_list.inputs = {}
 module_list.output = nil
 
@@ -45,7 +62,7 @@ function module_list:init(opt)
    for k, v in pairs(config) do
       log.printf(log.DEBUG, "              config['%s'] = '%s'", k, v)
    end
-   self.output = self:load(class):new(config)
+   self.output = self.classes[class]:new(config)
 
    for idx, input in ipairs(opt.cmd_ins) do
       local class, config = self:parse_config(input)
@@ -54,26 +71,12 @@ function module_list:init(opt)
       for k, v in pairs(config) do
          log.printf(log.DEBUG, "                config['%s'] = '%s'", k, v)
       end
-      table.insert(self.inputs, self:load(class):new(config))
+      table.insert(self.inputs, self.classes[class]:new(config))
    end
 
    return defines.OK
 end
 
-function module_list:load(class)
-   local old_path = package.path
-   package.path = "./modules/?.lua"
-
-   if(self.classes[class] == nil) then 
-      log.printf(log.DEBUG, "load module class: %s", class)
-      self.classes[class] = require(class) 
-   end
-
-   package.path = old_path
-
-   return self.classes[class]
-end
-
 function module_list:parse_config(module_config)
    local class, config_string = string.match(module_config, "^([%w-_]+):(.+)$")
    if(not class or not config_string) then