33 lines
948 B
Scheme
33 lines
948 B
Scheme
;;; 5-7.ms
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;;; Copyright 1984-2016 Cisco Systems, Inc.
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;;;
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;;; Licensed under the Apache License, Version 2.0 (the "License");
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;;; you may not use this file except in compliance with the License.
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;;; You may obtain a copy of the License at
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;;;
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;;; http://www.apache.org/licenses/LICENSE-2.0
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;;;
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;;; Unless required by applicable law or agreed to in writing, software
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;;; distributed under the License is distributed on an "AS IS" BASIS,
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;;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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;;; See the License for the specific language governing permissions and
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;;; limitations under the License.
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(mat box
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(box? (box 3))
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(equal? (box 'a) '#&a)
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(equal? (box '(a b c)) '#&(a b c))
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(not (eq? (box '()) (box '())))
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)
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(mat unbox
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(equal? (unbox '#&3) 3)
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(equal? (unbox (box 3)) 3)
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)
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(mat set-box!
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(let ((x (box 3)))
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(set-box! x 4)
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(and (equal? x '#&4) (equal? (unbox x) 4)))
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)
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