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