[Haskell-cafe] Re: ByteString comparison question (was: another Newbie performance question)

Philip Müller wrote:

Achim Schneider schrieb:

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Philip Müller wrote:

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I do not know how to compare a Word8 to a Char. Or maybe I don't need to?

You don't need to, just use ByteString.Char8 or ByteString.Lazy.Char8.

Could you give a short example of how to check whether a ByteString starts with a comma (',')?

import Parsec import Parsec.ByteString.Lazy check s = runParser (char ',') () "" s ;)

But now I get strange errors when compiling, like

Main.o: In function `rTD_info': (.text+0x5a): undefined reference to `bytestringzm0zi9zi1zi0_DataziByteStringziInternal_zdf2_closure'

Is this a problem with my Code or is it just GHC unable to find the ByteString package?

No, it can find it, or you would have gotten errors beforehand. The linker can't find it because GHC can be kind of demented when it comes to remembering which packages it used while compiling, depending on options/processing mode. use ghc -package bytestring or, preferably, ghc --make -- (c) this sig last receiving data processing entity. Inspect headers for past copyright information. All rights reserved. Unauthorised copying, hiring, renting, public performance and/or broadcasting of this signature prohibited.