From: David Vázquez <davazp@gmail.com>
Date: Mon, 6 May 2013 12:23:11 +0000 (+0100)
Subject: value argument is optional in defvar
X-Git-Url: http://repo.macrolet.net/gitweb/?a=commitdiff_plain;h=aef5df75dde094072f75f1f88e13c34710dc7a86;p=jscl.git

value argument is optional in defvar
---

diff --git a/src/boot.lisp b/src/boot.lisp
index 3ba4fda..ccb6f9b 100644
--- a/src/boot.lisp
+++ b/src/boot.lisp
@@ -60,10 +60,10 @@
 (defmacro unless (condition &body body)
   `(if ,condition nil (progn ,@body)))
 
-(defmacro defvar (name value &optional docstring)
+(defmacro defvar (name &optional (value nil value-p) docstring)
   `(progn
      (declaim (special ,name))
-     (unless (boundp ',name) (setq ,name ,value))
+     ,@(when value-p `((unless (boundp ',name) (setq ,name ,value))))
      ,@(when (stringp docstring) `((oset ',name "vardoc" ,docstring)))
      ',name))