test-suite/tests/dynamic-scope.test

   1 ;;;;                                                          -*- scheme -*-
   2 ;;;; dynamic-scop.test --- test suite for dynamic scoping constructs
   3 ;;;;
   4 ;;;; Copyright (C) 2001, 2006 Free Software Foundation, Inc.
   5 ;;;;
   6 ;;;; This program is free software; you can redistribute it and/or modify
   7 ;;;; it under the terms of the GNU General Public License as published by
   8 ;;;; the Free Software Foundation; either version 2, or (at your option)
   9 ;;;; any later version.
  10 ;;;;
  11 ;;;; This program is distributed in the hope that it will be useful,
  12 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;;;; GNU General Public License for more details.
  15 ;;;;
  16 ;;;; You should have received a copy of the GNU General Public License
  17 ;;;; along with this software; see the file COPYING.  If not, write to
  18 ;;;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  19 ;;;; Boston, MA 02110-1301 USA
  20
  21 (define-module (test-suite test-dynamic-scope)
  22   :use-module (test-suite lib))
  23
  24
  25 (define exception:missing-expr
  26   (cons 'syntax-error "Missing expression"))
  27 (define exception:bad-binding
  28   (cons 'syntax-error "Bad binding"))
  29 (define exception:duplicate-binding
  30   (cons 'syntax-error "Duplicate binding"))
  31
  32 (define global-a 0)
  33 (define (fetch-global-a) global-a)
  34
  35 (with-test-prefix "dynamic scope"
  36
  37   (pass-if "@bind binds"
  38     (= (@bind ((global-a 1)) (fetch-global-a)) 1))
  39
  40   (pass-if "@bind unbinds"
  41     (begin
  42       (set! global-a 0)
  43       (@bind ((global-a 1)) (fetch-global-a))
  44       (= global-a 0)))
  45
  46   (pass-if-exception "duplicate @binds"
  47     exception:duplicate-binding
  48     (eval '(@bind ((a 1) (a 2)) (+ a a))
  49           (interaction-environment)))
  50
  51   (pass-if-exception "@bind missing expression"
  52     exception:missing-expr
  53     (eval '(@bind ((global-a 1)))
  54           (interaction-environment)))
  55
  56   (pass-if-exception "@bind bad bindings"
  57     exception:bad-binding
  58     (eval '(@bind (a) #f)
  59           (interaction-environment)))
  60
  61   (pass-if-exception "@bind bad bindings"
  62     exception:bad-binding
  63     (eval '(@bind ((a)) #f)
  64           (interaction-environment)))
  65
  66   (pass-if "@bind and dynamic-wind"
  67     (letrec ((co-routine #f)
  68              (spawn (lambda (proc)
  69                       (set! co-routine proc)))
  70              (yield (lambda (val)
  71                       (call-with-current-continuation
  72                        (lambda (k)
  73                          (let ((next co-routine))
  74                            (set! co-routine k)
  75                            (next val)))))))
  76
  77       (spawn (lambda (val)
  78                (@bind ((global-a 'inside))
  79                  (yield global-a)
  80                  (yield global-a))))
  81
  82       (set! global-a 'outside)
  83       (let ((inside-a (yield #f)))
  84         (let ((outside-a global-a))
  85           (let ((inside-a2 (yield #f)))
  86             (and (eq? inside-a 'inside)
  87                  (eq? outside-a 'outside)
  88                  (eq? inside-a2 'inside))))))))
  89
  90
  91