As a newcomer to XC5, I have been looking for suitable training materials to familiarise myself with the OO tools used to construct and maintain XC5.
I have come across a really good, well paced and structured training video for Symphony 3, which includes the elements of Doctrine, Twig etc.
https://www.lynda.com/PHP-tutorials/Learning-Symfony-3/557776-2.html
You will need to pay Lynda.com to watch the video, but I feel it is well worth it if you are serious about developing with XC5.
I hope this helps?
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John Legg
www.TheDebugStore.com
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