From c1fbc5ab70c5be3eba3d451e37fbc896dcb7e2ce Mon Sep 17 00:00:00 2001
From: Gerd Heber <gheber@hdfgroup.org>
Date: Sat, 8 Aug 2015 09:12:49 -0500
Subject: [PATCH] Added DEF macro to define dynamic variables in user space and
 get around the 'undefined variable' warnings when using SETF without prior
 variable declaration.

---
 package.lisp    |  1 +
 src/macros.lisp | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/package.lisp b/package.lisp
index 9ea85c1..42b1442 100644
--- a/package.lisp
+++ b/package.lisp
@@ -405,6 +405,7 @@
 	   CPRD
 	   CRPR
 	   D
+	   DEF
 	   F
 	   DFFR
 	   DGNL
diff --git a/src/macros.lisp b/src/macros.lisp
index b6c27b0..fae82f5 100644
--- a/src/macros.lisp
+++ b/src/macros.lisp
@@ -6,6 +6,25 @@
 
 (PROVIDE "macros")
 
+
+;;;
+;;; UTILITIES
+
+
+(defmacro def (name value)
+  (declare (type symbol name))
+  "-----------------------------------------------------------------[macro-doc]
+DEF
+Args: (name value)
+Defines a dynamic variable NAME in the CL-USER package, assigns it VALUE,
+and returns VALUE.
+------------------------------------------------------------------------------"
+  `(progn
+     (intern (symbol-name ',name))
+     (defparameter ,name nil)
+     (setq ,name ,value)))
+
+
 ;;;
 ;;;  VARIOUS
 ;;;