Revision b009f682 src/Ganeti/Utils.hs
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, rStripSpace |
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, newUUID |
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, clockTimeToString |
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, chompPrefix |
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) where |
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import Data.Char (toUpper, isAlphaNum, isDigit, isSpace) |
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-- | Convert a ClockTime into a (seconds-only) timestamp. |
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clockTimeToString :: ClockTime -> String |
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clockTimeToString (TOD t _) = show t |
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{-| Strip a prefix from a string, allowing the last character of the prefix
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(which is assumed to be a separator) to be absent from the string if the string |
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terminates there. |
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>>> chompPrefix "foo:bar:" "a:b:c" |
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Nothing |
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>>> chompPrefix "foo:bar:" "foo:bar:baz" |
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Just "baz" |
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>>> chompPrefix "foo:bar:" "foo:bar:" |
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Just "" |
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>>> chompPrefix "foo:bar:" "foo:bar" |
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Just "" |
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>>> chompPrefix "foo:bar:" "foo:barbaz" |
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Nothing |
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-} |
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chompPrefix :: String -> String -> Maybe String |
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chompPrefix pfx str = |
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if pfx `isPrefixOf` str || str == init pfx |
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then Just $ drop (length pfx) str |
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else Nothing |
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