Fix for TAB in REPL, and BACKTAB going to previous error

2 files changed, 18 insertions, 2 deletions

diff --git a/doc/cheat.texi b/doc/cheat.texi
index 6087949..d83a540 100644
--- a/doc/cheat.texi
+++ b/doc/cheat.texi
@@ -110,6 +110,13 @@
 @item M-.
 @tab geiser-edit-symbol-at-point
 @tab Edit identifier at point
+@item TAB
+@tab geiser-completion--tab
+@tab Complete identifier at point or indent if none; away from
+last prompt, go to next error in the buffer.
+@item S-TAB (backtab)
+@tab geiser-completion--previous-error
+@tab Go to previous error in the REPL buffer
 @item TAB, M-TAB
 @tab geiser-completion--complete-symbol
 @tab Complete identifier at point
diff --git a/elisp/geiser-repl.el b/elisp/geiser-repl.el
index 57111f4..b84613b 100644
--- a/elisp/geiser-repl.el
+++ b/elisp/geiser-repl.el
@@ -505,11 +505,19 @@ With a prefix argument, force exit by killing the scheme process."
                (insert "\n"))))))
 
 (defun geiser-repl--tab (n)
+  "If we're after the last prompt, complete symbol or indent (if
+there's no symbol at point). Otherwise, go to next error in the REPL
+buffer."
   (interactive "p")
   (if (> (point) (geiser-repl--last-prompt-end))
       (geiser-completion--maybe-complete)
     (compilation-next-error n)))
 
+(defun geiser-repl--previous-error (n)
+  "Go to previous error in the REPL buffer."
+  (interactive "p")
+  (compilation-next-error (- n)))
+
 (define-derived-mode geiser-repl-mode comint-mode "REPL"
   "Major mode for interacting with an inferior scheme repl process.
 \\{geiser-repl-mode-map}"
@@ -535,13 +543,14 @@ With a prefix argument, force exit by killing the scheme process."
 (define-key geiser-repl-mode-map [return] 'geiser-repl--maybe-send)
 (define-key geiser-repl-mode-map "\C-j" 'geiser-repl--newline-and-indent)
 (define-key geiser-repl-mode-map (kbd "TAB") 'geiser-repl--tab)
+(define-key geiser-repl-mode-map [backtab] 'geiser-repl--previous-error)
 
 (define-key geiser-repl-mode-map "\C-a" 'geiser-repl--bol)
 (define-key geiser-repl-mode-map (kbd "<home>") 'geiser-repl--bol)
 
 (geiser-menu--defmenu repl geiser-repl-mode-map
-  ("Complete symbol" ((kbd "TAB") (kbd "M-TAB"))
-   geiser-completion--complete-symbol :enable (symbol-at-point))
+  ("Complete symbol" ((kbd "M-TAB"))
+   geiser-repl--tab :enable (symbol-at-point))
   ("Complete module name" ((kbd "C-.") (kbd "M-`"))
    geiser-completion--complete-module :enable (symbol-at-point))
   ("Edit symbol" "\M-." geiser-edit-symbol-at-point