25 lines
962 B
Text
25 lines
962 B
Text
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A library wrapping Prelude/Data.List functions that can throw exceptions, such
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as head and !!. Each unsafe function has up to four variants, e.g. with tail:
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* tail :: [a] -> [a], raises an error on tail [].
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* tailMay :: [a] -> Maybe [a], turns errors into Nothing.
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* tailDef :: [a] -> [a] -> [a], takes a default to return on errors.
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* tailNote :: String -> [a] -> [a], takes an extra argument which supplements
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the error message.
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* tailSafe :: [a] -> [a], returns some sensible default if possible,
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[] in the case of tail.
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This package is divided into three modules:
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* Safe contains safe variants of Prelude and Data.List functions.
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* Safe.Foldable contains safe variants of Foldable functions.
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* Safe.Exact creates crashing versions of functions like zip (errors if
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the lists are not equal) and take (errors if there are not enough elements),
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then wraps them to provide safe variants.
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