Rename env variable kak_curr_history_id to kak_history_id

README.asciidoc

@@ -792,7 +792,7 @@ Some of Kakoune state is available through environment variables:
  * `kak_buf_line_count`: the current buffer line count
  * `kak_timestamp`: timestamp of the current buffer, the timestamp is an
        integer value which is incremented each time the buffer is modified.
- * `kak_curr_history_id`: history id of the current buffer, the history id is an integer value
+ * `kak_history_id`: history id of the current buffer, the history id is an integer value
        which is used to reference a specific buffer version in the undo tree
  * `kak_runtime`: directory containing the kak binary
  * `kak_count`: count parameter passed to the command

doc/manpages/expansions.asciidoc

@@ -74,7 +74,7 @@ informations about Kakoune's state:
 *kak_timestamp*::
 	timestamp of the current buffer, the timestamp is an integer value
 	which is incremented each time the buffer is modified
-*kak_curr_history_id*::
+*kak_history_id*::
 	history id of the current buffer, the history id is an integer value
 	which is used to reference a specific buffer version in the undo tree
 *kak_runtime*::

src/main.cc

@@ -94,7 +94,7 @@ void register_env_vars()
             [](StringView name, const Context& context) -> String
             { return to_string(context.buffer().timestamp()); }
         }, {
-            "curr_history_id", false,
+            "history_id", false,
             [](StringView name, const Context& context) -> String
             { return to_string(context.buffer().current_history_id()); }
         }, {