Convert the whole site to use Pelican instead of Jekyll

content/blog/2016-02-26-vala-interface-madness.rst

@@ -0,0 +1,32 @@
+Vala interface madness
+######################
+
+:date: 2016-02-26T13:07:52Z
+:category: blog
+:tags: vala,development
+:url: 2016/02/26/vala-interface-madness/
+:save_as: 2016/02/26/vala-interface-madness/index.html
+:status: published
+:author: "Gergely Polonkai"
+
+Although I have just started making it in C, I decided to move my Matrix GLib SDK to Vala.  First
+to learn a new language, and second because it is much easier to write GObject based stuff with
+it.
+
+For the first step I created a ``.vapi`` file from my existing sources, so the whole SDK prototype
+was available for me in Vala.
+
+I had a ``MatrixEvent`` class that implemented the ``GInitable`` interface, and many others were
+subclassed ``MatrixEvent``.  For some reason I don’t remember, I created the following header for
+one of the event classes:
+
+.. code-block:: vala
+
+   public class MatrixPresenceEvent : GLib.Object, GLib.Initable {
+
+This is nice and everything, but as I didn’t create an ``init()`` method for
+``MatrixPresenceEvent``, it tried to use the one from the parent class and somehow got into an
+infinite loop.  The Vala transformer (``valac``), however, doesn’t mention this.
+
+Lessons learned: if you implement an interface on a subclass that is implemented by the parent
+don’t forget to add the necessary functions to the subclass.