Merge remote-tracking branch 'origin/stable-2.0'

[bpt/guile.git] / module / ice-9 / history.scm

diff --git a/module/ice-9/history.scm b/module/ice-9/history.scm
index 921a257..ebf609b 100644 (file)
--- a/module/ice-9/history.scm
+++ b/module/ice-9/history.scm
@@ -1,9 +1,9 @@
-;;;;   Copyright (C) 2000, 2001, 2004, 2006 Free Software Foundation, Inc.
+;;;;   Copyright (C) 2000, 2001, 2004, 2006, 2010 Free Software Foundation, Inc.
 ;;;; 
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
 ;;;; License as published by the Free Software Foundation; either
-;;;; version 2.1 of the License, or (at your option) any later version.
+;;;; version 3 of the License, or (at your option) any later version.
 ;;;; 
 ;;;; This library is distributed in the hope that it will be useful,
 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -17,9 +17,15 @@
 \f
 ;;;; A simple value history support
 
-(define-module (ice-9 history))
+(define-module (ice-9 history)
+  #:export (value-history-enabled? enable-value-history! disable-value-history!
+            clear-value-history!))
 
-(process-define-module '((value-history)))
+(define-module* '(value-history))
+
+(define *value-history-enabled?* #f)
+(define (value-history-enabled?)
+  *value-history-enabled?*)
 
 (define (use-value-history x)
   (module-use! (current-module)
@@ -37,5 +43,23 @@
            (module-export! history (list s))
            (set! count c))))))
 
-(add-hook! before-eval-hook use-value-history)
-(add-hook! before-print-hook save-value-history)
+(define (enable-value-history!)
+  (if (not (value-history-enabled?))
+      (begin
+        (add-hook! before-eval-hook use-value-history)
+        (add-hook! before-print-hook save-value-history)
+        (set! *value-history-enabled?* #t))))
+
+(define (disable-value-history!)
+  (if (value-history-enabled?)
+      (begin
+        (remove-hook! before-eval-hook use-value-history)
+        (remove-hook! before-print-hook save-value-history)
+        (set! *value-history-enabled?* #f))))
+
+(define (clear-value-history!)
+  (let ((history (resolve-module '(value-history))))
+    (hash-clear! (module-obarray history))
+    (hash-clear! (module-obarray (module-public-interface history)))))
+
+(enable-value-history!)