-(defvar scheme-program-name "scheme"
- "*Program invoked by the `run-scheme' command.")
-
-(defvar scheme-band-name nil
- "*Band loaded by the `run-scheme' command.")
-
-(defvar scheme-program-arguments nil
- "*Arguments passed to the Scheme program by the `run-scheme' command.")
-
-(defvar xscheme-allow-pipelined-evaluation t
+(defgroup xscheme nil
+ "Major mode for editing Scheme and interacting with MIT's C-Scheme."
+ :group 'lisp)
+
+(defcustom scheme-program-name "scheme"
+ "*Program invoked by the `run-scheme' command."
+ :type 'string
+ :group 'xscheme)
+
+(defcustom scheme-band-name nil
+ "*Band loaded by the `run-scheme' command."
+ :type '(choice (const nil) string)
+ :group 'xscheme)
+
+(defcustom scheme-program-arguments nil
+ "*Arguments passed to the Scheme program by the `run-scheme' command."
+ :type '(choice (const nil) string)
+ :group 'xscheme)
+
+(defcustom xscheme-allow-pipelined-evaluation t