linenoise: command to force submission of unbalanced line.

* linenoise.c (edit): Handle Ctrl-F in extended mode so that
Ctrl-X Ctrl-F forces the line to be submitted without a
balance check.

* txr.1: Document previously undocumented balance check,
including the flashing exclamation mark. Document Ctrl-X
Ctrl-F.

2 files changed, 14 insertions, 2 deletions

diff --git a/linenoise/linenoise.c b/linenoise/linenoise.c
index e61ba49d..78a3446f 100644
--- a/linenoise/linenoise.c
+++ b/linenoise/linenoise.c
@@ -2212,12 +2212,14 @@ static int edit(lino_t *l, const wchar_t *prompt)
                     }
                     break;
                 }
+                /* fallthrough */
+                l->save_hist_idx = l->history_index;
+            case CTL('F'):
+                ret = l->len;
                 if (l->mlmode)
                     edit_move_end(l);
                 if (l->need_refresh)
                     refresh_line(l);
-                ret = l->len;
-                l->save_hist_idx = l->history_index;
                 goto out;
             case '?':
                 extended = 0;
diff --git a/txr.1 b/txr.1
index c7cf620d..72466bf5 100644
--- a/txr.1
+++ b/txr.1
@@ -71427,6 +71427,16 @@ such a line
 .B is
 entered into the history.
 
+The listener does not allow lines containing certain bad syntax to be submitted
+with Enter.  If the buffer contains an expression with unbalanced parentheses
+or brackets, or unterminated literals, then Enter generates a newline character
+which is inserted into the buffer. In that situation, if that newline character
+is being added at the very end of the buffer, the listener flashes the
+exclamation mark character (!) two times to warn the user that line has not
+been submitted: no computation is taking place, and the listener is waiting for
+more input.  It is possible to force the submission of an unbalanced line using
+the sequence Ctrl-X, Ctrl-F.
+
 .SS* Limitations
 
 The interactive listener can only accept up to 4095 abstract characters of