Introduce a library for configurable options

part of darcs patch: Sat Sep 17 18:35:54 EEST 2005  Eric Knauel <knauel@informatik.uni-tuebingen.de>

scheme/config.scm

@@ -0,0 +1,53 @@
+(define *configuration* '())
+
+(define (init-config config-file)
+  (with-input-file 
+   config-file
+   (set! *configuration* (read))))
+(define (read-config config-file)
+  (call-with-input-file config-file read))
+
+(define (config option)
+  (let ((probe (assq option *configuration*)))
+(define (config-file-to-use)
+  (let ((from-env (getenv "CMDRSRC"))
+	(default-location
+	  (string-append (home-dir) "/.cmdrsrc")))
+    (if (and from-env (file-exists? from-env))
+	from-env
+	default-location)))
+
+(define (read-config-file!)
+  (with-errno-handler
+   ((errno data)
+    (else #f))
+   (let ((conf-file (config-file-to-use)))
+     (for-each
+      (lambda (option.value)
+	(cond
+	 ((and (pair? option.value)
+	       (pair? (car option.value))
+	       (symbol? (caar option.value))
+	       (symbol? (cdar option.value))
+	       (assoc (car option.value) *configuration*))
+	  => (lambda (p)
+	       (set-cdr! p (cdr option.value))))
+	 (else
+	  (error "Unknown option value or ill-formed option" 
+		 option.value conf-file))))
+      (read-config conf-file)))))
+
+(define (config module option)
+  (let ((probe (assoc (cons module option) *configuration*)))
+    (if probe 
+        (cdr probe)
+        (error "unknown configuration option" option))))
+
+(define (define-option module option-name default-value)
+  (set! *configuration*
+	(cons (cons (cons module option-name) default-value)
+	      *configuration*)))
+	
+
+
+

scheme/nuit-engine.scm

@@ -16,6 +16,18 @@
 	 (release-lock lock)
 	 val)))))
 
+;; configurable options
+
+(define-option 'main 'switch-command-buffer-mode-key key-f7)
+
+;; configurable options
+
+(define-option 'main 'switch-command-buffer-mode-key key-f7)
+
+;; configurable options
+
+(define-option 'main 'switch-command-buffer-mode-key key-f7)
+
 ;; mode of the command buffer
 (define *command-buffer-mode* initial-command-mode)
 
@@ -308,6 +320,8 @@
 
   (init-screen)
   (init-windows!)
+  (read-config-file!)
+
   (clear)
 
   (if (not (process-group-leader?))
@@ -365,7 +379,7 @@
 	(loop (wait-for-input) #f maybe-selector)))
 
      ;; F7 toggle scheme-mode / command-mode (FIXME: find a better key)
-     ((= ch key-home)
+     ((= ch (config 'main 'switch-command-buffer-mode-key))
       (toggle-command/scheme-mode)
       (loop (wait-for-input) #f #f))
 

scheme/nuit-packages.scm

@@ -756,6 +756,19 @@
 	command-line-absyn)
   (files comp-cmd))
    
+;;; config
+
+(define-interface configuration-interface
+  (export read-config-file!
+	  define-option
+	  config))
+
+(define-structure configuration configuration-interface
+  (open scheme-with-scsh
+	signals
+	handle-fatal-error)
+  (files config))
+
 ;;; nuit 
 
 (define-interface nuit-interface
@@ -791,6 +804,7 @@
 	initial-tty
 	nuit-windows 
 
+	configuration
 	command-line-parser
 	focus-table
 	result-buffer-changes