Improved cache system for resources and more things.

[gacela.git] / src / utils.scm

diff --git a/src/utils.scm b/src/utils.scm
new file mode 100644 (file)
index 0000000..17d1bbf
--- /dev/null
+++ b/src/utils.scm
@@ -0,0 +1,33 @@
+;;; Gacela, a GNU Guile extension for fast games development
+;;; Copyright (C) 2009 by Javier Sancho Fernandez <jsf at jsancho dot org>
+;;;
+;;; This program is free software: you can redistribute it and/or modify
+;;; it under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation, either version 3 of the License, or
+;;; (at your option) any later version.
+;;;
+;;; This program is distributed in the hope that it will be useful,
+;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+(define-module (gacela utils)
+  #:export (use-cache-with))
+
+
+;;; Cache for procedures
+
+(define (use-cache-with proc)
+  (let ((cache (make-weak-value-hash-table)))
+    (lambda (. param)
+      (let* ((key param)
+            (res (hash-ref cache key)))
+       (cond (res res)
+             (else
+              (set! res (apply proc param))
+              (hash-set! cache key res)
+              res))))))