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</o:shapelayout></xml><![endif]--></head><body lang=NL link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi all,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>The program reads lots of small Text files. readCDFile handles the encoding. Below is the simplest version of readCDFile.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>If I call readCDFile "/home/kees/freeDB/inputError/" "blah" (the file blah does not exist) I get:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Left "MyError: /home/kees/freeDB/inputError/blah: openBinaryFile: does not exist (No such file or directory)". The exception is caught by exceptionHandler<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>If I call readCDFile "/home/kees/freeDB/inputError/" "67129209" I get freeDB: Cannot decode byte '\xa0': Data.Text.Internal.Encoding.decodeUtf8: Invalid UTF-8 stream. The exception is not caught by exceptionHandler (No “MyError: ” in front). The file 67129209 is indeed bad encoded.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I’am using SomeException. Still, this ‘bad encoding exception’ is not caught. Why?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Kees<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>qualified</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> Data.Text </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>as</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> T<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> System.FilePath.Posix<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>qualified</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> Data.Text.Encoding </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>as</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> TE<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>qualified</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> Data.ByteString.Lazy </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>as</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> B<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> Prelude </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>hiding</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> (</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#DCDCAA;mso-fareast-language:NL'>catch</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>)<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>import</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> Control.Exception<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p> </o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#DCDCAA;mso-fareast-language:NL'>main</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>::</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>IO</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> ()<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>main = </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#C586C0;mso-fareast-language:NL'>do</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> res <- readCDFile </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#CE9178;mso-fareast-language:NL'>"/home/kees/freeDB/inputError/"</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#CE9178;mso-fareast-language:NL'>"67129209"</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> <o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> print res<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p> </o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#DCDCAA;mso-fareast-language:NL'>readCDFile</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>::</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>FilePath</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>-></span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>FilePath</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>-></span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>IO</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> (</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>Either</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>String</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>T</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>.</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>Text</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>)<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>readCDFile baseDir fn = </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#C586C0;mso-fareast-language:NL'>do</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> catch ( </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#C586C0;mso-fareast-language:NL'>do</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> <o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> buffer <- B.readFile (combine baseDir fn)<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>let</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> bufferStrict = B.toStrict buffer<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> return $ Right $ TE.decodeUtf8 bufferStrict<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> ) exceptionHandler<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p> </o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#DCDCAA;mso-fareast-language:NL'>exceptionHandler</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>::</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>SomeException</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>-></span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>IO</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> (</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>Either</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>String</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>T</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>.</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>Text</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>)<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>exceptionHandler e = </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#C586C0;mso-fareast-language:NL'>do</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#569CD6;mso-fareast-language:NL'>let</span><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> err = show e<o:p></o:p></span></p><p class=MsoNormal style='line-height:14.25pt;background:#1E1E1E'><span lang=EN-US style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> </span><span style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'>return $ Left $ </span><span style='font-size:10.5pt;font-family:Consolas;color:#CE9178;mso-fareast-language:NL'>"MyError: "</span><span style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'> ++ err<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:12.0pt;line-height:14.25pt;background:#1E1E1E'><span style='font-size:10.5pt;font-family:Consolas;color:#D4D4D4;mso-fareast-language:NL'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br /> <table style="border-top: 1px solid #D3D4DE;">
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