add a video

docs/videos.md

@@ -44,6 +44,24 @@ At the end and to make obvious the automatic aspect of a library selection, the
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+### Programming sessions - parse enum in YATOL
+
+This video shows a full programming session during which i add a new grammar construct to my toy programming language.
+There are 3 parts:
+
+1. The formal grammar (i use a PEG that can be used in Pegged) is updated.
+2. The hand written parser is updated.
+3. Changes are pushed on line and i wait for TravisCI to start (which didn't happen !).
+
+{% raw %}
+<iframe src="https://player.vimeo.com/video/222057562" width="640" height="480" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
+{% endraw %}
+
+The video illustrate well that the [runnable](features_runnables) modules (the command Run module unittest is a subset of the feature) are valuable.
+The PEG can be tested on the fly because pegged is registered in the libman.
+The parser can be tested on the fly because the compiler (as a library) is registered in the libman.
+The custom tools allows to easily push changes online.
+
 
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