123 lines
1.7 KiB
Markdown
123 lines
1.7 KiB
Markdown
Strings
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=======
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```haskell
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import qualified Data.Text as T
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import qualified Data.Text.Lazy as L
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```
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Text
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----
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The Text type represents Unicode character strings, in a time and space-efficient manner. This package provides text processing capabilities that are optimized for performance critical use, both in terms of large data quantities and high speed.
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LText
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-----
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Bytestring
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----------
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LBytestring
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-----------
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Encoding
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----------
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#### encodeUtf8
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```haskell
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encodeUtf8 :: Text -> ByteString
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```
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```haskell
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> encodeUtf8 "ポケット"
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"\227\131\157\227\130\177\227\131\131\227\131\136"
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```
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#### decodeUtf8
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```haskell
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decodeUtf8 :: ByteString -> Text
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```
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```haskell
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> putStrLn $ decodeUtf8 "\227\131\157\227\130\177\227\131\131\227\131\136"
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ポケット
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```
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#### decodeUtf8'
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```haskell
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decodeUtf8' :: ByteString -> Either UnicodeException Text
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```
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#### decodeUtf8With
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```haskell
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decodeUtf8With :: OnDecodeError -> ByteString -> Text
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```
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#### UnicodeException
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```haskell
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data UnicodeException
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= DecodeError [Char] (Maybe Word8)
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| EncodeError [Char] (Maybe Char)
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```
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Strictness
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----------
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#### fromStrict
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```haskell
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fromStrict :: Text -> LText
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```
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#### toStrict
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```haskell
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toStrict :: LText -> Text
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```
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Conversion
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----------
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```haskell
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class StringConv a b where
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strConv :: Leniency -> a -> b
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data Leniency = Lenient | Strict
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```
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#### toS
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```haskell
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toS :: StringConv a b => a -> b
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```
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#### toSL
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```haskell
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toSL :: StringConv a b => a -> b
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```
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*Example*:
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```haskell
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a :: LByteString
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a = "Einstein"
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b :: Text
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b = "Feynmann"
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c :: ByteString
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c = "Schrödinger"
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example1 :: ByteString
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example1 = toS b
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example2 :: Bool
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example2 = (a == toS b) && (toS b == c)
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```
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