Add: DEFPARAMETER

diff --git a/ecmalisp.lisp b/ecmalisp.lisp
index 76a189e..6c173b9 100644 (file)
--- a/ecmalisp.lisp
+++ b/ecmalisp.lisp
@@ -38,8 +38,23 @@
                                                    ,@body)))
                             ',name))))
 
+  (setq nil 'nil)
+  (setq t 't)
+
+  (defmacro when (condition &body body)
+    `(if ,condition (progn ,@body) nil))
+
+  (defmacro unless (condition &body body)
+    `(if ,condition nil (progn ,@body)))
+
   (defmacro defvar (name value)
     `(progn
+       (unless (boundp ',name)
+        (setq ,name ,value))
+       ',name))
+
+  (defmacro defparameter (name value)
+    `(progn
        (setq ,name ,value)
        ',name))
 
@@ -57,9 +72,6 @@
 
   (defvar *package* (new))
 
-  (defvar nil 'nil)
-  (defvar t 't)
-
   (defun null (x)
     (eq x nil))
 
@@ -131,12 +143,6 @@
   (defmacro push (x place)
     `(setq ,place (cons ,x ,place)))
 
-  (defmacro when (condition &body body)
-    `(if ,condition (progn ,@body) nil))
-
-  (defmacro unless (condition &body body)
-    `(if ,condition nil (progn ,@body)))
-
   (defmacro dolist (iter &body body)
     (let ((var (first iter))
           (g!list (gensym)))