[STUMP] [PATCH] Fix `eval-line' for the case when the user aborts

When the user aborts, pressing C-g for example, `cmd' is NIL, so
`read-from-string' will trow a TYPE-ERROR.

`colon', the command which reads further commands from the user, use
the form (unless cmd (throw 'error :abort)) for the case of a user
aborting.  Although this makes for a nice "Abort." message to the
user, it breaks evaling (colon) from the REPL and pressing C-g,
because the tag `'error' doesn't exist.
---

I think there is a deep fix here.

`colon' works nicely when called by a keybind because StumpWM has in
the call stack `eval-command', which checks for a result of `:abort'
and then prints "Abort.".

Using `call-interactively' protects the caller from the nonexistent
tag because it wraps command using the tag `'error'.

There might be a way to integrate this calling conventions, so
whichever the user aborts inside a input box, "Abort." is print and
there is no error thrown.

 user.lisp |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/user.lisp b/user.lisp
index 63b65ae..f630292 100644
--- a/user.lisp
+++ b/user.lisp
@@ -175,9 +175,10 @@ such a case, kill the shell command to resume StumpWM."
 (defcommand eval-line (cmd) ((:rest "Eval: "))
   "Evaluate the s-expression and display the result(s)."
   (handler-case
-      (message "^20~{~a~^~%~}"
-               (mapcar 'prin1-to-string
-                       (multiple-value-list (eval (read-from-string cmd)))))
+      (when cmd
+        (message "^20~{~a~^~%~}"
+                 (mapcar 'prin1-to-string
+                         (multiple-value-list (eval (read-from-string cmd))))))
     (error (c)
       (err "^B^1*~A" c))))
 
-- 
1.7.10.4