diff --git a/source/dyaml/loader.d b/source/dyaml/loader.d
index 6d0b811..33ae4db 100644
--- a/source/dyaml/loader.d
+++ b/source/dyaml/loader.d
@@ -380,9 +380,9 @@ struct Loader
 
 unittest
 {
-    char[] yaml_input = "red:   '#ff0000'\n"
-                        "green: '#00ff00'\n"
-                        "blue:  '#0000ff'".dup;
+    char[] yaml_input = ("red:   '#ff0000'\n" ~
+                        "green: '#00ff00'\n" ~
+                        "blue:  '#0000ff'").dup;
 
     auto colors = Loader.fromString(yaml_input).load();