r7061: initial property settings

[kmrcl.git] / macros.lisp

diff --git a/macros.lisp b/macros.lisp
index 03e3a9fd1240cea47ee7a45ceff53e0c13037280..835c6d91bcac3cffabaf49d425fe1a623a02c1d6 100644 (file)
--- a/macros.lisp
+++ b/macros.lisp
@@ -7,7 +7,7 @@
 ;;;; Programmer:    Kevin M. Rosenberg
 ;;;; Date Started:  Apr 2000
 ;;;;
-;;;; $Id: macros.lisp,v 1.2 2003/06/06 21:59:29 kevin Exp $
+;;;; $Id$
 ;;;;
 ;;;; This file, part of KMRCL, is Copyright (c) 2002 by Kevin M. Rosenberg
 ;;;;
@@ -164,3 +164,26 @@
             (print-seconds secs)
             (format t ", time per iteration: ")
             (print-seconds (coerce (/ secs ,n) 'double-float))))))))
+
+(defmacro mv-bind (vars form &body body)
+  `(multiple-value-bind ,vars ,form 
+     ,@body))
+
+;; From USENET
+(defmacro deflex (var val &optional (doc nil docp))    
+  "Defines a top level (global) lexical VAR with initial value VAL,
+      which is assigned unconditionally as with DEFPARAMETER. If a DOC
+      string is provided, it is attached to both the name |VAR| and the
+      name *STORAGE-FOR-DEFLEX-VAR-|VAR|* as a documentation string of
+      kind 'VARIABLE. The new VAR will have lexical scope and thus may
+      be shadowed by LET bindings without affecting its global value."
+  (let* ((s0 (load-time-value (symbol-name '#:*storage-for-deflex-var-)))
+        (s1 (symbol-name var))
+        (p1 (symbol-package var))
+        (s2 (load-time-value (symbol-name '#:*)))
+        (backing-var (intern (concatenate 'string s0 s1 s2) p1)))
+    `(progn
+      (defparameter ,backing-var ,val ,@(when docp `(,doc)))
+      ,@(when docp
+             `((setf (documentation ',var 'variable) ,doc)))
+      (define-symbol-macro ,var ,backing-var))))