diff --git a/src/command-line.lisp b/src/command-line.lisp
index 30ececf..affe4fb 100644
--- a/src/command-line.lisp
+++ b/src/command-line.lisp
@@ -155,12 +155,12 @@
            (write-sequence (text-utils:join-with-strings sequence " ")
                            *standard-output*))
          (build-options (all-options switch-prefix key)
-           (remove-if (lambda (a) (string= a switch-prefix))
-                      (mapcar (lambda (a) (format nil
-                                                  "~a~a"
-                                                  switch-prefix
-                                                  (getf a key "")))
-                              all-options))))
+           (let ((compatible-options (mapcar (lambda (a) (getf a key))
+                                             (remove-if-not (lambda (a) (getf a key nil))
+                                                            all-options))))
+             (mapcar (lambda (a)
+                       (format nil "~a~a" switch-prefix a))
+                     compatible-options))))
     (let* ((all-options   (options))
            (long-options  (build-options all-options "--" :long))
            (short-options (build-options all-options "-"  :short))
@@ -175,10 +175,13 @@
                (length words))
             (let ((matched (sort (remove-if-not (lambda (a)
                                                   (cl-ppcre:scan (strcat "^"
-                                                                         (elt words words-index))
+                                                                         (elt words
+                                                                              words-index))
                                                                  a))
                                                 options)
-                                 (lambda (a b) (< (length a) (length b))))))
+                                 (lambda (a b)
+                                   (< (length a)
+                                      (length b))))))
               (if matched
                   (progn
                     (write-shell-array matched))