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<a name="treesitter-mainVideo-transcript"></a>
# Transcript

[[!template new="1" text="""Hey everyone, my name is Abin Simon""" start="00:00:00.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and this talk is about &quot;Tree-sitter:""" start="00:00:03.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Beyond Syntax Highlighting.&quot;""" start="00:00:05.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For those who are not aware of what Tree-sitter is,""" start="00:00:08.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""let me give you a quick intro.""" start="00:00:10.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Tree-sitter, at its core, is a parser generator tool""" start="00:00:11.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and an incremental parsing library.""" start="00:00:17.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""What it essentially means is that it gives you""" start="00:00:19.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""an always up-to-date""" start="00:00:22.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""AST [abstract syntax tree] of your code.""" start="00:00:23.155" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""In the current Emacs frame, what you see to the right""" start="00:00:24.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""is the AST tree produced by Tree-sitter""" start="00:00:27.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""of the code that is on the left.""" start="00:00:30.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For example, if you go to this &quot;if&quot; statement,""" start="00:00:33.560" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""you can see it goes here.""" start="00:00:37.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It is also really good at handling errors.""" start="00:00:38.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For example, if I were to delete this [if statement],""" start="00:00:41.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""it still parses out a tree as much as it can,""" start="00:00:44.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but with an error node.""" start="00:00:47.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Now let's see how we can query the tree""" start="00:00:50.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to get the information that we need.""" start="00:00:51.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's first try to get all the identifiers in the buffer.""" start="00:00:54.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It highlights all the identifiers in the buffer,""" start="00:01:01.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but let's say we want to get something""" start="00:01:04.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""a little more precise.""" start="00:01:05.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's say we wanted to get this &quot;i&quot; here.""" start="00:01:07.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This, in our case, would be this identifier""" start="00:01:10.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""inside this assignment expression""" start="00:01:13.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""inside this &quot;for&quot; statement.""" start="00:01:15.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""We can write it out like this.""" start="00:01:27.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I hope this gives you a basic idea""" start="00:01:29.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""of how Tree-sitter works and how you can query""" start="00:01:31.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to get the information that you need.""" start="00:01:34.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""First of all, let's see how Tree-sitter can help us""" start="00:01:37.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""with syntax highlighting.""" start="00:01:39.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is the default syntax highlighting by Emacs for SQL.""" start="00:01:41.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now let's see how Tree-sitter helps.""" start="00:01:46.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is the syntax highlighting in Emacs""" start="00:01:52.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""which Tree-sitter enabled.""" start="00:01:54.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""You'll see that we're able to target""" start="00:01:56.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""a lot more things and highlight them.""" start="00:01:58.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""That said, you don't always have to""" start="00:02:01.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""highlight everything.""" start="00:02:03.139" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I personally prefer a much simpler theme.""" start="00:02:04.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Now let's see how Tree-sitter helps you simplify""" start="00:02:15.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""adding custom syntax highlighting to your code.""" start="00:02:17.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is a Python file which has""" start="00:02:20.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""a class and a few member functions.""" start="00:02:22.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Anyone who has used Python will know that""" start="00:02:25.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""the &quot;self&quot; keyword, while it is passed in as an argument,""" start="00:02:27.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""it has more meaning than that.""" start="00:02:32.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's see if you can use Tree-sitter""" start="00:02:34.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to highlight just the &quot;self&quot; keyword.""" start="00:02:35.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""If you look at the Tree-sitter tree,""" start="00:02:38.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""you can see that this is the first identifier""" start="00:02:40.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""in the list of parameters for a function definition.""" start="00:02:43.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is how you would query for the first identifier""" start="00:02:45.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""inside parameters inside a function definition.""" start="00:02:55.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now, if you see here, it also matches &quot;cls&quot;,""" start="00:02:59.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but let's restrict it to match just &quot;self&quot;.""" start="00:03:02.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now we have a Tree-sitter query that identifies""" start="00:03:11.360" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""the first argument to the function definition""" start="00:03:14.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and is also called &quot;self&quot;.""" start="00:03:16.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""We can use this to apply custom highlighting onto this.""" start="00:03:19.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is pretty much all the code""" start="00:03:22.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that you'll need to do this.""" start="00:03:25.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""The first block here is essentially to say to""" start="00:03:26.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Tree-sitter to highlight anything with python.self""" start="00:03:29.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""with the face of custom-set.""" start="00:03:32.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now the second block here essentially is""" start="00:03:35.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""how we match for that.""" start="00:03:37.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now if you go back into a Python buffer""" start="00:03:39.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and re-enable python-mode, we'll see that &quot;self&quot;""" start="00:03:41.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""is highlighted differently.""" start="00:03:44.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""How about creating text objects?""" start="00:03:47.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Tree-sitter can help there too.""" start="00:03:48.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For those who don't know, text objects""" start="00:03:50.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""is an idea that comes from Vim,""" start="00:03:53.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and you can do things like select word,""" start="00:03:54.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""delete word, things like that.""" start="00:03:57.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""There are other text objects like line and paragraph.""" start="00:04:00.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For each text object, you can have operations""" start="00:04:06.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that are defined on them.""" start="00:04:09.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For example, delete, copy, select, comment,""" start="00:04:09.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""all of these are operations that you can do.""" start="00:04:13.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's try and use Tree-sitter to add more text objects.""" start="00:04:16.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is a plugin that I wrote""" start="00:04:19.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""which lets you add more text objects into Emacs.""" start="00:04:20.560" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It helps you code aware text objects""" start="00:04:25.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""like functions, conditionals, loops, and such.""" start="00:04:27.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's see an example scenario of how""" start="00:04:31.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""something like this could come in handy.""" start="00:04:34.360" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For example, I can select inside this condition""" start="00:04:35.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""or inside this function and do things like that.""" start="00:04:39.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's say I want to take this conditional,""" start="00:04:42.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""move to the next function, and create it here.""" start="00:04:44.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""What I would do is something like""" start="00:04:47.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""delete the conditional, move to the next function,""" start="00:04:49.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""create a conditional there, and paste.""" start="00:04:52.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's try another example.""" start="00:04:56.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's say I want to take this and move it to the end.""" start="00:04:57.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""If I had to do it without text objects,""" start="00:05:01.360" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I'd probably have to go back to the previous comma,""" start="00:05:02.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""delete till next comma, find the closing bracket,""" start="00:05:06.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and paste before.""" start="00:05:10.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""That works, but let's see""" start="00:05:11.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""how Tree-sitter can simplify it.""" start="00:05:14.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""With Tree-sitter, I can say delete the argument,""" start="00:05:16.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""go to the end of the next argument, and then paste.""" start="00:05:19.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Tree-sitter essentially helps Emacs""" start="00:05:22.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""understand the code better semantically.""" start="00:05:25.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Here is yet another use case.""" start="00:05:27.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I work at a remote company,""" start="00:05:29.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and I often find myself being in a call""" start="00:05:31.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""with my teammates, explaining the code to them.""" start="00:05:33.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""And one thing that really comes in handy""" start="00:05:35.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""is the narrowing capability of Emacs.""" start="00:05:38.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Specifically, the fancy-narrow package.""" start="00:05:39.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I use it to narrow just the function,""" start="00:05:43.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""or I could narrow to the conditional.""" start="00:05:44.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Next to the end, the list would be code folding.""" start="00:05:48.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is a package which uses Tree-sitter""" start="00:05:51.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to improve the code folding functionalities of Emacs.""" start="00:05:54.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Code folding has always been this thing""" start="00:05:57.560" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that I've had a love-hate relationship with.""" start="00:06:00.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It usually works most of the time,""" start="00:06:02.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but then fails if the indentation is wrong""" start="00:06:04.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""or we do something weird with the arguments.""" start="00:06:06.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""But now with Tree-sitter in the mix,""" start="00:06:09.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""it's a lot more precise.""" start="00:06:11.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I can fold comments, I can fold functions,""" start="00:06:12.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I can fold conditionals. You get the idea.""" start="00:06:17.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""I work with Kubernetes, which means I end up""" start="00:06:20.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""having to write and read a lot of YAML files.""" start="00:06:23.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""And navigating big YAML files is a mess.""" start="00:06:28.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""The two main problems are figuring out where I am,""" start="00:06:31.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and two, navigating to where I want to be.""" start="00:06:35.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's see how Tree-sitter can help us with both of this.""" start="00:06:38.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is an example YAML file.""" start="00:06:41.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""To be precise, this is the values file""" start="00:06:43.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""of the Redis helm chart.""" start="00:06:47.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I'm somewhere in the file on tag under image,""" start="00:06:48.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but I don't know what this tag is for.""" start="00:06:52.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""But with the help of Tree-sitter,""" start="00:06:54.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I've been able to add this information""" start="00:06:57.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""into my header line.""" start="00:06:59.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""If you see in the header line,""" start="00:07:00.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""you'll see that I'm under sentinel.image.""" start="00:07:02.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Now let's see how this helps with navigation.""" start="00:07:05.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's say I want to enable persistence on master node.""" start="00:07:08.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""So with the help of Tree-sitter,""" start="00:07:12.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I was able to enumerate every field""" start="00:07:18.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that is available in this YAML file,""" start="00:07:20.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and I can pass that information onto imenu,""" start="00:07:22.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""which I can then use to go to exactly where I want to.""" start="00:07:24.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Also, since we're not dealing with""" start="00:07:28.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""any language specific constructs,""" start="00:07:30.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""this is very easy to extend to""" start="00:07:32.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""other similar languages""" start="00:07:34.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""or config files in this case.""" start="00:07:35.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""So for example, this is a JSON file,""" start="00:07:37.440" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and I can navigate to location or project.""" start="00:07:39.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""And just like in YAML, it shows me where I'm at.""" start="00:07:44.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I'm in projects.name,""" start="00:07:48.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""or I'm inside projects.highlights.""" start="00:07:49.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Or how about Nix?""" start="00:07:52.880" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is my home.nix file.""" start="00:07:55.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Again, I can search for services,""" start="00:07:57.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and this lists me all the services that I've enabled.""" start="00:08:01.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""How about just services.description?""" start="00:08:04.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""So this is all the services""" start="00:08:06.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that I've enabled and have descriptions.""" start="00:08:08.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Now that we have seen this for config files,""" start="00:08:10.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""let's see how similar things apply for code.""" start="00:08:12.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Just like in config files,""" start="00:08:15.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I can see which function I'm under,""" start="00:08:16.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and if I go to the next function, it changes.""" start="00:08:18.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Okay, here is something really awesome.""" start="00:08:21.560" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This is probably one of my favorites,""" start="00:08:23.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and one of the things that actually made me understand""" start="00:08:26.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""how powerful Tree-sitter is, and got me into it.""" start="00:08:30.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I work with a lot of Go code,""" start="00:08:34.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and anyone who has worked with Go will tell you""" start="00:08:35.680" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""how repetitive it is handling errors.""" start="00:08:38.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""For those who don't write Go,""" start="00:08:41.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""let me give you a rough idea of what I'm talking about.""" start="00:08:42.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""If you want to bubble up the error,""" start="00:08:45.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""the way you would do it is just to return the error""" start="00:08:47.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to the function that called it.""" start="00:08:49.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Over here, you can either return nil or an empty value,""" start="00:08:51.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and at the end, you return error.""" start="00:08:55.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Let's try and use Tree-sitter to do this.""" start="00:08:57.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Using the help of Tree-sitter, let's make Emacs""" start="00:09:00.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""go back, figure out what the return arguments are,""" start="00:09:03.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""figure out what their default values are,""" start="00:09:06.422" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and automatically fill in the return statement.""" start="00:09:08.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It would look something like this.""" start="00:09:11.480" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""In my case, it filled in the complete form,""" start="00:09:13.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""it figured out what the return arguments are,""" start="00:09:16.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""what their types are,""" start="00:09:18.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and what their default values are,""" start="00:09:19.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and filled out the entire return.""" start="00:09:20.960" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""And since this is a template,""" start="00:09:22.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I can go to the next function, do the same thing,""" start="00:09:24.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""next function, do the same thing,""" start="00:09:27.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""next function, do the same thing.""" start="00:09:29.560" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""Here is a really fascinating use case of Tree-sitter,""" start="00:09:31.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""structural editing.""" start="00:09:34.360" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""You might be aware of plugins like paredit,""" start="00:09:36.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""which seems to &quot;know&quot; your code.""" start="00:09:38.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""This sort of takes it onto another level.""" start="00:09:40.280" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It is in its early stages, but what this lets you do""" start="00:09:42.520" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""is completely treat your code as an AST,""" start="00:09:46.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and edit as if it's a tree instead of characters.""" start="00:09:48.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""I am not going to go much in depth into it,""" start="00:09:52.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but if you're interested, there is a talk""" start="00:09:54.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""from last year's EmacsConf around it.""" start="00:09:57.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""I'm just going to end this with one last tiny thing""" start="00:09:59.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that I found in the tree-sitter-extras package.""" start="00:10:02.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It's this tiny macro called tree-sitter-save-excursion.""" start="00:10:04.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It works pretty much like save-excursion, but better.""" start="00:10:07.600" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It uses the Tree-sitter syntax tree""" start="00:10:11.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""instead of just the code""" start="00:10:13.400" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""to figure out where to restore the position.""" start="00:10:14.800" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""My main use case for this was with code formatters.""" start="00:10:16.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""Since the code moves around a lot""" start="00:10:20.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""when it gets formatted,""" start="00:10:22.080" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""save-excursion was completely useless,""" start="00:10:23.160" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""but this came in handy.""" start="00:10:25.000" video="mainVideo-treesitter" id="subtitle"]]
[[!template new="1" text="""I'll just leave you off with""" start="00:10:26.240" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""what the future of Tree-sitter looks like for Emacs.""" start="00:10:28.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""So far, every Tree-sitter related feature""" start="00:10:31.120" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""that I've talked about is powered by this library.""" start="00:10:33.760" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""But there is talk about Tree-sitter coming into the core.""" start="00:10:36.040" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""It will most probably be landing in Emacs 29,""" start="00:10:42.320" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""and if you want to check out the work on Tree-sitter""" start="00:10:45.840" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""in core Emacs, you can check out""" start="00:10:48.720" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""the features/tree-sitter branch.""" start="00:10:51.200" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""You'll probably see more and more features and packages""" start="00:10:52.920" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""relying upon Tree-sitter, and even major modes""" start="00:10:56.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""being powered by Tree-sitter.""" start="00:10:59.640" video="mainVideo-treesitter" id="subtitle"]]
[[!template text="""And that's a wrap from me. Thank you.""" start="00:11:01.560" video="mainVideo-treesitter" id="subtitle"]]



Captioner: sachac

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