From: Mark Wooding <mdw@distorted.org.uk>
Date: Sun, 22 May 2011 14:07:33 +0000 (+0100)
Subject: frontend.lisp: Hack around CLisp's bizarreness.
X-Git-Url: https://git.distorted.org.uk/~mdw/zone/commitdiff_plain/afb5d9e651733a0e7aacf42f892422931041f637

frontend.lisp: Hack around CLisp's bizarreness.

Annoyingly, CLisp's PROBE-FILE signals an error if you give it a
directory name.  Bodge around this.  I pinched the basic idea from
the CL-FAD package, by Peter Seibel and Edi Weitz.
---

diff --git a/frontend.lisp b/frontend.lisp
index 1ff3e2f..7801a8a 100644
--- a/frontend.lisp
+++ b/frontend.lisp
@@ -33,9 +33,28 @@
 (defvar opt-format :bind
   "Which format to use on output.")
 
+(defun directory-exists-p (name)
+  
+  ;; Make a pathname for NAME which has the right form for a directory.
+  (let ((dirpath
+	 (let ((path (pathname name)))
+	   (if (null (pathname-name path))
+	       path
+	       (make-pathname :directory 
+			      (append (or (pathname-directory path)
+					  (list :relative))
+				      (list (pathname-name path)))
+			      :name nil
+			      :type nil
+			      :defaults path)))))
+
+    ;; Now check that it exists.
+    #+clisp (and (ext:probe-directory dirpath) (truename dirpath))
+    #-clisp (probe-file dirpath)))
+
 (eval-when (:compile-toplevel :load-toplevel)
   (defopthandler dir (var arg) ()
-    (let ((path (probe-file arg)))
+    (let ((path (directory-exists-p arg)))
       (if (and path
 	       (not (pathname-name path)))
 	  (setf var path)