1Prelude.Maybe(3kaya) Kaya module reference Prelude.Maybe(3kaya)
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6 Prelude::Maybe - Optional values.
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9 Prelude::Maybe< a >
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12 = nothing()
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15 | just(a val)
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18 A value is either of type a , represented as just(a) , or empty. Maybe
19 is often useful for computations which can possibly fail, for example
20 looking up values in a dictionary. Because the nothing value can be
21 stored, this is often more useful than Exceptions on failure.
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24 Kaya standard library by Edwin Brady, Chris Morris and others
25 (kaya@kayalang.org). For further information see http://kayalang.org/
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28 The Kaya standard library is free software; you can redistribute it
29 and/or modify it under the terms of the GNU Lesser General Public
30 License (version 2.1 or any later version) as published by the Free
31 Software Foundation.
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34 Prelude.deref (3kaya)
35 Dict.lookup (3kaya)
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39Kaya December 2010 Prelude.Maybe(3kaya)