author | bulwahn |
Thu, 07 Jul 2011 23:33:14 +0200 | |
changeset 43704 | 47b0be18ccbe |
parent 38840 | ec75dc58688b |
child 43719 | ba1b2c918c32 |
permissions | -rw-r--r-- |
38840 | 1 |
/* Title: Pure/Concurrent/volatile.scala |
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Author: Makarius |
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Volatile variables. |
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*/ |
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package isabelle |
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class Volatile[A](init: A) |
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{ |
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@volatile private var state: A = init |
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def peek(): A = state |
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def change(f: A => A) { state = f(state) } |
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def change_yield[B](f: A => (B, A)): B = |
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{ |
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val (result, new_state) = f(state) |
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state = new_state |
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result |
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} |
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} |
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