lib: add RFC-145 nixdoc comments to extended library functions

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I41c4b2cb70512699a044578fa88eb8266a6a6964

lib/lua.nix

@@ -1,7 +1,57 @@
 # Helpers for converting values to lua
 {lib}: let
+  /**
+    Test whether an object is a `luaInline` value (i.e. has `_type == "lua-inline"`).
+
+    # Type
+
+    ```
+    isLuaInline :: Any -> Bool
+    ```
+
+    # Arguments
+
+    - `object`: Any Nix value.
+
+    # Example
+
+    ```nix
+    isLuaInline (lib.mkLuaInline "vim.fn.getcwd()")
+    => true
+
+    isLuaInline "just a string"
+    => false
+    ```
+  */
   isLuaInline = object: (object._type or null) == "lua-inline";
 
+  /**
+    Recursively convert a Nix value to its Lua representation as a string.
+
+    Handles all primitive Nix types as well as lists, attribute sets,
+    derivations (rendered as their store path string), and `luaInline` values
+    (rendered verbatim). Null attributes are stripped from sets.
+
+    # Type
+
+    ```
+    toLuaObject :: Any -> String
+    ```
+
+    # Arguments
+
+    - `args`: Any Nix value to convert.
+
+    # Example
+
+    ```nix
+    toLuaObject { a = 1; b = true; c = null; }
+    => ''{["a"] = 1,\n["b"] = true}''
+
+    toLuaObject [ "x" "y" ]
+    => ''{"x",\n"y"}''
+    ```
+  */
   toLuaObject = args:
     {
       int = toString args;
@@ -42,6 +92,30 @@
 in
   {
     inherit isLuaInline toLuaObject;
+
+    /**
+      Convert a list of Lua expression strings into a Lua table string.
+
+      Each element is wrapped with `mkLuaInline` before conversion so that
+      strings are treated as raw Lua rather than quoted string literals.
+
+      # Type
+
+      ```
+      luaTable :: [String] -> String
+      ```
+
+      # Arguments
+
+      - `x`: List of Lua expression strings.
+
+      # Example
+
+      ```nix
+      luaTable [ "vim.fn.getcwd()" "vim.fn.expand('%')" ]
+      => ''{vim.fn.getcwd(),\nvim.fn.expand('%')}''
+      ```
+    */
     luaTable = x: (toLuaObject (map lib.mkLuaInline x));
   }
   // lib.genAttrs [