Reading from Text and ByteString

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BSD-3-Clause licensed by Doug Beardsley
Maintained by


The Read type class is very useful for building data types from String representations. But String has high overhead, so sometimes it isn’t suitable for applications where space usage and performance are important. This library provides a simpler version of Read’s functionality for Text and UTF8 encoded ByteStrings.



  • Reinstate Text and ByteString instances because some users require them.

  • Add yes/no and y/n parsing to the Bool instance


  • Remove Readable instances for ByteString and Text because they are probably not what the user wants and could cause compilation to succeed when you probably want to see an error.

  • Fix fromBS for ByteString so it is a correct passthrough instead of doing encodeUtf8 . decodeUtf8 under the hood.

  • Use decodeUtf8’ so that we can catch character encoding exceptions and return mzero instead of generating an exception.