cca3bad0bb
`Prelude.lean` has no dependencies, and at the end of `Prelude`, the `syntax` and `macro` commands are operational.
31 lines
787 B
Text
31 lines
787 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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Authors: Leonardo de Moura
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-/
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prelude
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import Init.Data.UInt
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import Init.Data.String
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universes u
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instance : Hashable Nat := {
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hash := fun n => USize.ofNat n
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}
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instance {α β} [Hashable α] [Hashable β] : Hashable (α × β) := {
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hash := fun (a, b) => mixHash (hash a) (hash b)
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}
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protected def Option.hash {α} [Hashable α] : Option α → USize
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| none => 11
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| some a => mixHash (hash a) 13
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instance {α} [Hashable α] : Hashable (Option α) := {
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hash := fun
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| none => 11
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| some a => mixHash (hash a) 13
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}
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instance {α} [Hashable α] : Hashable (List α) := {
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hash := fun as => as.foldl (fun r a => mixHash r (hash a)) 7
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}
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