Add submodule and apply syntax highlighting theme

Author: hedyhli

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "tree-sitter-cognate"]
+	path = tree-sitter-cognate
+	url = https://github.com/hedyhli/tree-sitter-cognate

highlights.scm

@@ -0,0 +1,40 @@
+(number) @number
+(string) @string
+(escape_sequence) @string.escape
+(symbol) @constant
+(boolean) @boolean
+
+[(line_comment) (multiline_comment)] @comment
+(inline_comment) @comment.inline
+
+";" @punctuation.special
+
+["(" ")"] @punctuation.bracket
+
+(identifier) @variable
+
+(statement
+ (identifier) @keyword (#eq? @keyword "Def")
+ .
+ (identifier) @function)
+
+;; TODO: Update once neovim supports this.
+; ((identifier) @function (#is-not? local))
+
+((identifier) @keyword.special (#any-of? @keyword.special "Def" "Let" "Set"))
+
+((identifier) @keyword (#any-of? @keyword "For" "While" "When" "If"
+                        "Case" "When" "Unless" "Do" "With" "Take-while"
+                        "Until"))
+
+((identifier) @function.builtin (#any-of? @function.builtin
+                                "Empty" "Match" "Print" "Put" "Random" "Modulo" "Sqrt" "Integer?" "Zero?" "First" "Rest" "Head" "Tail" "Push" "Empty?" "Join" "String-length" "Substring" "Regex" "Regex-match" "Ordinal" "Character" "Split" "Uppercase" "Lowercase" "Floor" "Round" "Ceiling" "Abs" "Error" "Wait" "Stop" "Show" "Stack" "Clear" "Unbox" "Debug" "Begin" "Sind" "Cosd" "Tand" "Sin" "Cos" "Tan" "Exp" "Log" "Ln" "Asind" "Acosd" "Atand" "Asin" "Acos" "Atan" "Sinhd" "Coshd" "Tanhd" "Sinh" "Cosh" "Tanh" "Table" "Insert" "Remove" "." "Has" "Values" "Keys" "Parameters" "Input" "Open" "Read-file" "Read-line" "Close" "Path" "Seek" "Drop" "Prepend" "Index" "All" "Discard" "None" "Append" "Swap" "Fold" "Prints" "Times" "Range" "Twin" "Take" "Triplet" "Min" "Reverse" "Filter" "Max" "Map" "Puts" "Sort" "Assert" "Length" "Of"
+                                 ))
+((identifier) @operator (#any-of? @operator "+" "-" "*" "/" ">" "<" "<=" ">=" "^"
+                         "==" "!=" "Not" "And" "Or" "Xor"))
+((identifier) @type.builtin (#any-of? @type.builtin "List" "Box" "Number" "Number!" "String!" "List!" "Block!" "Symbol!" "Boolean!" "Box!" "Io!" "Any!" "Number?" "String?" "List?" "Block?" "Symbol?" "Boolean?" "Box?" "Io?" "Any?"))
+
+(statement (
+  (identifier) @function.builtin (#eq? @function.builtin ".")
+  .
+  (identifier) @variable.member))

public/index.html

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
 
-tree-sitter highlight --scope source.cog -H /dev/stdin | sed -z '
+tree-sitter highlight --query-paths $PWD/highlights.scm --config-path tree-sitter.json --scope source.cog -H /dev/stdin | sed -z '
   s/.*<table>\n\(.*\)\n<\/table>.*/\1/
   s/<tr><td class=line-number>[0-9]\+<\/td><td class=line>\([^\n]*\)\n<\/td><\/tr>/\1/g'

public/learn/index.html

@@ -0,0 +1,45 @@
+{
+  "parser-directories": [
+    "."
+  ],
+  "theme": {
+    "function": "#795da3",
+    "function.builtin": "#183691",
+    "attribute": {
+      "italic": true,
+      "color": 124
+    },
+    "keyword": "#a71d5d",
+    "number": "#0086b3",
+    "punctuation.delimiter": 239,
+    "variable.parameter": {
+      "underline": true
+    },
+    "operator": {
+      "bold": true,
+      "color": 239
+    },
+    "tag": 18,
+    "constructor": 136,
+    "string": "#183691",
+    "variable": "#795da3",
+    "comment": {
+      "color": "#969896",
+      "italic": true
+    },
+    "comment.inline": {
+      "color": "#333333",
+      "italic": false
+    },
+    "module": 136,
+    "string.special": "#183691",
+    "variable.builtin": {
+      "bold": true
+    },
+    "type": "#794da3",
+    "property": 124,
+    "keyword.special": "#0086b3",
+    "embedded": null,
+    "punctuation.bracket": 239
+  }
+}