[gnome-boxes] CodingStyle: add rulez about multiple returned values

[Marc-Andre Lureau <malureau src gnome org>]

commit d1a36c6f0afdc9bd830cc6b86be987b1e3f9b170
Author: Marc-Andrà Lureau <marcandre lureau gmail com>
Date:   Wed Jul 18 14:40:46 2012 +0200

    CodingStyle: add rulez about multiple returned values
    
    Some proposal to spice up the day while Zeeshan is on holiday :)
    Just kidding, we should try to convince him in GUADEC!
    
     * If a function returns several equally important values, they should
       all be given as out arguments. IOW, prefer this:
    
         void get_a_and_b (out string a, out string b)
    
       rather than the un-even, string get_a_and_b (out b)
    
    https://bugzilla.gnome.org/show_bug.cgi?id=680166

 CodingStyle.txt     |    7 +++++++
 src/vm-creator.vala |   10 ++++------
 2 files changed, 11 insertions(+), 6 deletions(-)
---
diff --git a/CodingStyle.txt b/CodingStyle.txt
index d58aaf2..3aff76d 100644
--- a/CodingStyle.txt
+++ b/CodingStyle.txt
@@ -94,3 +94,10 @@ from the Rygel Coding Style.
     default:
         ...
     }
+
+ * If a function returns several equally important values, they should
+   all be given as out arguments. IOW, prefer this:
+
+     void get_a_and_b (out string a, out string b)
+
+   rather than the un-even, string get_a_and_b (out b)
diff --git a/src/vm-creator.vala b/src/vm-creator.vala
index f03dd60..83a1227 100644
--- a/src/vm-creator.vala
+++ b/src/vm-creator.vala
@@ -32,8 +32,8 @@ private class Boxes.VMCreator {
             yield;
         }
 
-        string title;
-        var name = yield create_domain_name_and_title_from_media (out title);
+        string title, name;
+        yield create_domain_name_and_title_from_media (out name, out title);
         yield install_media.prepare_for_installation (name, cancellable);
 
         var volume = yield create_target_volume (name, install_media.resources.storage);
@@ -152,13 +152,13 @@ private class Boxes.VMCreator {
         }
     }
 
-    private async string create_domain_name_and_title_from_media (out string title) throws GLib.Error {
+    private async void create_domain_name_and_title_from_media (out string name, out string title) throws GLib.Error {
         var base_title = install_media.label;
         title = base_title;
         var base_name = (install_media.os != null) ? install_media.os.short_id : base_title;
         if (install_media.live)
             base_name += "-live";
-        var name = base_name;
+        name = base_name;
 
         var pool = yield get_storage_pool ();
         for (var i = 2;
@@ -169,8 +169,6 @@ private class Boxes.VMCreator {
             name = base_name + "-" + i.to_string ();
             title = base_title + " " + i.to_string ();
         }
-
-        return name;
     }
 
     private async StorageVol create_target_volume (string name, int64 storage) throws GLib.Error {