Difference between revisions of "Array indexing: improved safety with modular arithmetic"
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(Created page with "Category:Proposals Instead of an error being triggered if an array access is outside its bounds: <pre> Prelude Data.Array> array (0, 1) (zip [0, 1] [False, True]) ! 2 *...") |
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| − | [[Category:Proposals]] |
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| − | Instead of an error being triggered if an array access is outside its bounds: |
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| − | <pre> |
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| − | Prelude Data.Array> array (0, 1) (zip [0, 1] [False, True]) ! 2 |
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| − | *** Exception: Ix{Integer}.index: Index (2) out of range ((0,1)) |
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| − | </pre> |
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| − | use the given index modulo the array's length: |
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| − | <pre> |
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| − | Prelude Data.Array> array (0, 1) (zip [0, 1] [False, True]) ! 2 |
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| − | False |
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| − | </pre> |
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| − | As an added benefit, accessing the end elements of an array would be simplified: |
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| − | <pre> |
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| − | Prelude Data.Array> [ array (0, 25) (zip [0..25] ['a'..'z']) ! n | n <- [-1, -2 .. -8] ] |
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| − | "zyxwvuts" |
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| − | </pre> |
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| − | [[User:Atravers|Atravers]] 04:54, 19 January 2019 (UTC) |
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