2021-06-04 13:56:03 +00:00
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;;; SPDX-License-Identifier: LGPL-3.0-or-later
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;;; SPDX-FileCopyrightText: Copyright © 2010-2021 Tony Garnock-Jones <tonyg@leastfixedpoint.com>
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2021-06-01 15:19:24 +00:00
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2020-04-27 18:27:48 +00:00
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#lang racket/base
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;; "Instance" protocol for discriminating among
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;; otherwise-indistinguishable entities.
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(provide (struct-out instance))
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;; (instance Any Any), assertion or message
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;;
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;; In cases where `spec` can have multiple instantiations, serves to
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;; distinguish between them. Each `id` should be unique within its
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;; scope.
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;;
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(struct instance (id spec) #:prefab)
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