Made it a module.

Put it in any directory, run guile -L . and then import (goof) in that directory.

goof/helpers.scm

@@ -0,0 +1,13 @@
+(define-module (goof helpers)
+  #:export (define-aux-syntax define-aux-syntaxes))
+
+(define-syntax define-aux-syntax
+  (lambda (stx)
+    (syntax-case stx ()
+      ((_ name)
+       #'(define-syntax name
+           (lambda (stx)
+             (syntax-violation 'name "Loop clause used outside of loop macro" stx)))))))
+(define-syntax-rule (define-aux-syntaxes name ...)
+  (begin
+    (define-aux-syntax name) ...))