From b1c7e7129458e4c3687dfae4b4fb5dd4ece32618 Mon Sep 17 00:00:00 2001
From: Revar Desmera <revarbat@gmail.com>
Date: Sun, 12 May 2019 10:59:59 -0700
Subject: [PATCH] Re-added is_def(){

---
 compat.scad | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/compat.scad b/compat.scad
index 439b9d4..6ac1ffb 100644
--- a/compat.scad
+++ b/compat.scad
@@ -21,6 +21,14 @@
 function default(v,dflt=undef) = is_undef(v)? dflt : v;
 
 
+// Function: is_def()
+// Usage:
+//   is_def(v)
+// Description:
+//   Returns true if `v` is not `undef`.  False if `v==undef`.
+function is_def(v) = !is_undef(v);
+
+
 // Function: is_vector()
 // Usage:
 //   is_vector(v)