diff --git a/src/lib.rs b/src/lib.rs
index e63cf1d..5ffddf9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -28,7 +28,7 @@ impl Default for Config {
 fn getenv(v: &str) -> Option<String> {
     use std::os::getenv;
     let r = getenv(v);
-    println!("{} = {}", v, r);
+    println!("{:?} = {:?}", v, r);
     r
 }