01/02: emacs: Fix converting scheme into elisp expression.

[Alex Kost]

alezost pushed a commit to branch master
in repository guix.

commit 4c68c538048803e47103d61a9dd855a0dc1187e2
Author: Alex Kost <address@hidden>
Date:   Sun Jan 24 11:16:44 2016 +0300

    emacs: Fix converting scheme into elisp expression.
    
    * emacs/guix-geiser.el (guix-geiser-eval-read): Replace #f/#t with nil/t
      only when they follow "(" or " ".
---
 emacs/guix-geiser.el |   22 +++++++++++++++++-----
 1 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/emacs/guix-geiser.el b/emacs/guix-geiser.el
index 0e6cc03..833f5bb 100644
--- a/emacs/guix-geiser.el
+++ b/emacs/guix-geiser.el
@@ -46,11 +46,23 @@ Return a list of strings with result values of evaluation."
 (defun guix-geiser-eval-read (str &optional repl)
   "Evaluate STR with guile expression using Geiser REPL.
 Return elisp expression of the first result value of evaluation."
-  ;; Parsing scheme code with elisp `read' is probably not the best idea.
-  (read (replace-regexp-in-string
-         "#f\\|#<unspecified>" "nil"
-         (replace-regexp-in-string
-          "#t" "t" (car (guix-geiser-eval str repl))))))
+  ;; The goal is to convert a string with scheme expression into elisp
+  ;; expression.
+  (let ((result (car (guix-geiser-eval str repl))))
+    (cond
+     ((or (string= result "#f")
+          (string= result "#<unspecified>"))
+      nil)
+     ((string= result "#t")
+      t)
+     (t
+      (read (replace-regexp-in-string
+             "[ (]\\(#f\\)" "nil"
+             (replace-regexp-in-string
+              "[ (]\\(#t\\)" "t"
+              result
+              nil nil 1)
+             nil nil 1))))))
 
 (defun guix-repl-send (cmd &optional save-history)
   "Send CMD input string to the current REPL buffer.