add Lua classes tutorial

content/treehouse/new.tree

@@ -26,7 +26,26 @@ if you've been wondering what I've been up to, you've come to the right place.
         if you want to read any of the posts, follow the links.
         it's like that by design.
 
+% tags = ["programming", "lua"]
+  id = "01JKKQZRSG5ZRNH530D75E2660"
+- ### [implementing classes in Lua][page:programming/lua/classes]
+
+    % id = "01JKKQZRSGXT99FJ7V3BGKE2D5"
+    - one of my absolutely favourite parts of Lua is how tiny, but capable it is.
+    did you know you could implement object-oriented programming without needing any additional syntactic support?
+
+    % id = "01JKKQZRSGMN81PXJWGP5Y17WY"
+    - this is a remaster of an [old tutorial I published as a Gist](https://gist.github.com/liquidev/3f37f94efdacd14a654a4bdc37c8008f) to explain how object-oriented programming works in Lua to someone on the [LÖVE](https://love2d.org/) Discord server.
+
+        % id = "01JKKQZRSGMW486TGSXQVM8FV3"
+        - thus there's a high likelihood you've never read it.
+        however, I think it's a pretty nice tutorial, so I'm republishing it here outside the shackles of GitHub.
+
+        % id = "01JKKQZRSGNA5NRXR5H6WPZKWA"
+        - and the programming trickery in it might just open your third eye a bit, so you should read it even if you're not into Lua!
+
 % id = "01JK5SN2ZBDZTFZ27J3KNT4SQV"
+  tags = ["music"]
 - ### [Floating Points - Tilt Shift / Ablaze][page:music/tilt-shift-ablaze]
 
     % id = "01JK5SNYKRK08F5DJM4JGBK4C4"
@@ -38,6 +57,7 @@ if you've been wondering what I've been up to, you've come to the right place.
     so that I can remember, and so the world can see, too...
 
 % id = "01JHXVRT2HR6TXC2V9JG2XTZVB"
+  tags = ["music"]
 - ### [The Flashbulb - Flacks / aBliss][page:music/flacks]
 
     % id = "01JHXVRT2H2CTGBEDYWCMDTTS3"