21 lines
467 B
Text
21 lines
467 B
Text
/-
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Copyright (c) 2016 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Author: Leonardo de Moura
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-/
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prelude
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import init.fin
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open nat
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definition char := fin 256
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namespace char
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definition of_nat [coercion] (n : nat) : char :=
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if H : n < 256 then fin.mk n H else fin.mk 0 dec_trivial
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end char
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definition char.has_decidable_eq [instance] : decidable_eq char :=
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have decidable_eq (fin 256), from _,
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this
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