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(* Title: Pure/ML-Systems/exn.ML
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ID: $Id$
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Author: Makarius
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Runtime exceptions as values.
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*)
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structure Exn =
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struct
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datatype 'a result =
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Result of 'a |
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Exn of exn;
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fun get_result (Result x) = SOME x
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| get_result _ = NONE;
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fun get_exn (Exn exn) = SOME exn
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| get_exn _ = NONE;
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fun capture f x = Result (f x) handle e => Exn e;
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fun release (Result y) = y
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| release (Exn e) = raise e;
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exception EXCEPTIONS of exn list * string;
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end;
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