Basic value setting now works

2 files changed, 56 insertions, 4 deletions

diff --git a/examples/change-setting.lua b/examples/change-setting.lua
index bff5889..3dd646e 100644
--- a/examples/change-setting.lua
+++ b/examples/change-setting.lua
@@ -14,11 +14,14 @@ project.head "refs/heads/jeff"
 other.thing "here"
 ]]
 
-conf = clod.parse(input_config)
+conf, err = clod.parse(input_config)
+if not conf then
+   error(err)
+end
 
 conf.settings.project.name = "Clod"
-conf.settings.project.head = "refs/heads/jeff"
+conf.settings.project.head = "refs/heads/master"
 conf.settings.project.description = "Demonstration of settings"
 
-print(conf:serialise())
+io.stdout:write(conf:serialise())
 
diff --git a/lib/clod.lua b/lib/clod.lua
index 7058ab3..4cabbf0 100644
--- a/lib/clod.lua
+++ b/lib/clod.lua
@@ -40,6 +40,55 @@ function settings_mt:__index(subkey)
    end
 end
 
+function settings_mt:__newindex(subkey, value)
+   local meta = metadata[self]
+   local confmeta = metadata[meta.conf]
+   local key = subkey
+   if meta.prefix then
+      key = meta.prefix .. "." .. subkey
+   end
+   if value == nil then
+      -- removing an entry...
+      if confmeta.settings[key] then
+	 -- Need to remove *this* entry
+	 local entry = confmeta.settings[key]
+	 if entry == confmeta.entries then
+	    -- First entry, move the head along
+	    confmeta.entries = entry.next
+	 end
+	 if entry.prev then
+	    entry.prev.next = entry.next
+	 end
+	 if entry.next then
+	    entry.next.prev = entry.prev
+	 end
+	 -- Shuffle all lines from here on down away
+	 entry = entry.next
+	 while entry do
+	    entry.lineno = entry.lineno - 1
+	    entry = entry.next
+	 end
+      end
+   elseif confmeta.settings[key] then
+      -- Replacing extant entry
+      confmeta.settings[key].value = value
+   else
+      -- Inventing a new entry, we will put it at the end
+      local last = confmeta.entries
+      while last.next do
+	 last = last.next
+      end
+      local new_entry = {
+	 key = key,
+	 value = value,
+	 lineno = last.lineno + 1,
+	 prev = last
+      }
+      last.next = new_entry
+      confmeta.settings[key] = new_entry
+   end
+end
+
 -- Helper routines
 function gen_settings(tab, prefix)
    local meta = metadata[tab]
@@ -113,7 +162,7 @@ local function parse_config(conf, confname)
       -- A 'local' indexing, so combine with the key
       return gen_hook(("%s.%s"):format(prefix, key))
    end
-   function parse_mt:__setindex(key, value)
+   function parse_mt:__newindex(key, value)
       -- This is the equivalent of 'foo = "bar"' instead of 'foo "bar"'
       return self[key](value)
    end