added error handling & you can save nil now

settings.moon

@@ -13,66 +13,93 @@ totype = (str) ->
 
 cache = {}
 
+get = (name, create=true) ->
+  setting = cache[name]
+  unless setting
+    setting = Settings\find :name
+    if (not setting) and create
+      setting = Settings\create :name
+    cache[name] = setting
+
+  if setting
+    return setting
+  else
+    return nil, "failed to load '#{name}' setting"
+
 local settings
 settings = {
-  get: (name, skip_index=false) ->
+  get: (name, skip_index) ->
     unless name
       return settings.load!
 
     unless skip_index -- for metamethods to not loop endlessly
       return settings[name] if settings[name]
-    setting = Settings\find :name
-    unless setting
-      setting = Settings\create :name
-    cache[name] = setting
-    val = totype setting.value
-    settings[name] = val
-    return val
+
+    setting, err = get name
+    if setting
+      value = totype setting.value
+      settings[name] = value
+      return value
+    else
+      return nil, err
 
   set: (name, value) ->
     unless name
       return settings.save!
 
-    setting = cache[name]
-    unless setting
-      setting = Settings\find :name
-    unless setting
-      setting = Settings\create :name
-    cache[name] = setting
-
-    if value ~= nil
+    setting, err = get name
+    if setting
       settings[name] = value
       return setting\update value: tostring value
     else
-      return setting\update value: tostring settings[name]
+      return nil, err
 
-  save: ->
+  save: (name) ->
+    if name
+      setting, err = get name
+      if setting
+        return setting\update value: tostring settings[name]
+      else
+        return nil, err
+
+    else
       for name, value in pairs settings
-      unless "function" == type value
+        switch name
+          when "get", "set", "save", "load", "delete"
+            nil
+          else
+            t = type value
+            if t == "function" or t == "table"
+              return nil, "cannot save '#{name}' setting, type '#{t}' not supported"
+            else
               unless cache[name]
                 cache[name] = Settings\find :name
                 unless cache[name]
                   cache[name] = Settings\create :name
 
-    for _, setting in pairs cache
-      setting\update value: tostring settings[setting.name]
+    for name, setting in pairs cache
+      _, err = setting\update value: tostring settings[name]
+      return nil, err if err
     return true
 
-  load: ->
+  load: (name) ->
+    return settings.get name if name
+
     all_settings = Settings\select "WHERE true"
     for setting in *all_settings
-      cache[setting.name] = setting
-      settings[setting.name] = totype setting.value
+      name = setting.name
+      cache[name] = setting
+      settings[name] = totype setting.value
     return settings
 
   delete: (name) ->
-    setting = cache[name]
-    unless setting
-      setting = Settings\find :name
-    if setting
-      setting\delete!
+    if setting = get name, false
+      if setting\delete!
         cache[name] = nil
         settings[name] = nil
+      else
+        return nil, "failed to delete '#{name}' setting"
+    return true
 }
 
 return setmetatable settings, {