PLT: evaluation functions moved to their own module.

1 files changed, 65 insertions, 0 deletions

diff --git a/scheme/plt/geiser/eval.ss b/scheme/plt/geiser/eval.ss
new file mode 100644
index 0000000..8fa5b81
--- /dev/null
+++ b/scheme/plt/geiser/eval.ss
@@ -0,0 +1,65 @@
+;; eval.ss -- evaluation
+
+;; Copyright (C) 2009 Jose Antonio Ortega Ruiz
+
+;; Author: Jose Antonio Ortega Ruiz <jao@gnu.org>
+;; Start date: Sun Apr 26, 2009 00:44
+
+;; This file 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 file 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/>.
+
+;;; Comentary:
+
+;; Evaluation functions
+
+;;; Code:
+
+#lang scheme
+
+(provide eval-in compile-in set-last-result)
+
+(require scheme/enter)
+
+(define last-result (void))
+(define nowhere (open-output-nowhere))
+
+(define (ensure-module spec)
+  (cond ((symbol? spec) spec)
+        ((not (string? spec)) #f)
+        ((not (file-exists? spec)) #f)
+        ((absolute-path? spec) `(file ,spec))
+        (else spec)))
+
+(define (exn-key e)
+  (vector-ref (struct->vector e) 0))
+
+(define (set-last-error e)
+  (set! last-result `((error (key . ,(exn-key e))
+                             (subr)
+                             (msg . ,(exn-message e))))))
+(define (set-last-result v)
+  (set! last-result `((result  ,v))))
+
+(define (eval-in form spec)
+  (set-last-result (void))
+  (with-handlers ((exn? set-last-error))
+    (parameterize ((current-error-port nowhere))
+      (eval #`(enter! #,(ensure-module spec))))
+    ((dynamic-require '(lib "geiser/eval")
+                      'set-last-result) (eval form)))
+  (enter! #f)
+  last-result)
+
+(define compile-in eval-in)
+
+;;; eval.ss ends here