Lua: rename `reader_extensions`/`writer_extensions` globals...

...as `Extensions`.

Update documnetation.

Include a custom extension in the documentation example.

See #8390.

1 files changed, 6 insertions, 5 deletions

diff --git a/doc/custom-readers.md b/doc/custom-readers.md
index 4d2009690..2d9938121 100644
--- a/doc/custom-readers.md
+++ b/doc/custom-readers.md
@@ -98,19 +98,20 @@ end
 Custom readers can be built such that their behavior is
 controllable through format extensions, such as `smart`,
 `citations`, or `hard-line-breaks`. Supported extensions are those
-that are present as a key in the global `reader_extensions` table.
+that are present as a key in the global `Extensions` table.
 Fields of extensions that are enabled default have the value
 `true`, while those that are supported but disabled have value
 `false`.
 
 Example: A writer with the following global table supports the
-extensions `smart` and `citations`, with the former enabled and
-the latter disabled by default:
+extensions `smart`, `citations`, and `foobar`, with `smart` enabled and
+the other two disabled by default:
 
 ``` lua
-reader_extensions = {
+Extensions = {
   smart = true,
   citations = false,
+  foobar = false
 }
 ```
 
@@ -129,7 +130,7 @@ end
 ```
 
 Extensions that are neither enabled nor disabled in the
-`reader_extensions` field are treated as unsupported by the
+`Extensions` field are treated as unsupported by the
 reader. Trying to modify such an extension via the command line
 will lead to an error.