Here's the Prelude imports I see at the moment. Didn't chase down the dependencies in all the code initially and now I see that GHC.Show does import GHC.List. Still, I suspect this has something to do with fusion nonetheless.
<div><br class="webkit-block-placeholder"></div><div><div>#ifdef __GLASGOW_HASKELL__</div><div>import GHC.Base</div><div>import GHC.IOBase</div><div>import GHC.Exception</div><div>import GHC.Read</div><div>import GHC.Enum
</div><div>import GHC.Num</div><div>import GHC.Real</div><div>import GHC.Float</div><div>import GHC.Show</div><div>import GHC.Err ( error, undefined )</div><div>#endif</div><div><br class="webkit-block-placeholder"></div>
<div>(from <a href="http://www.haskell.org/ghc/docs/latest/html/libraries/base/src/Prelude.html">http://www.haskell.org/ghc/docs/latest/html/libraries/base/src/Prelude.html</a>)</div><div><br class="webkit-block-placeholder">
</div><div>--s</div></div><div><br><br><div class="gmail_quote">On Dec 22, 2007 4:44 PM, Stefan O'Rear <<a href="mailto:stefanor@cox.net">stefanor@cox.net</a>> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="Ih2E3d">On Sat, Dec 22, 2007 at 04:40:00PM -0500, Sterling Clover wrote:<br>> I'm curious if you get the same performance difference importing<br></div>> GHC.Listinstead of<br><div class="Ih2E3d">>
Data.Char? I chased some dependencies, and Data.Char imports GHC.Arr, which<br>> in turn imports GHC.List, which provides a bunch of fusion rules pragmas<br>> that would probably optimize your (++) usage. If this is the case, not sure
<br>> if its a bug or not, but all this will have to be thought through as more<br>> stream fusion is rolled out anyway, I suspect?<br>> --S<br><br></div>The Prelude imports GHC.List, iirc.<br><font color="#888888">
<br>Stefan<br></font><br>-----BEGIN PGP SIGNATURE-----<br>Version: GnuPG v1.4.6 (GNU/Linux)<br><br>iD8DBQFHbYVTFBz7OZ2P+dIRAi02AJ41CyIVwCRLH2MU51Sc8Rjrtgxy+ACeL1m8<br>F2a0Id2PErsKgjOyggkT8Ig=<br>=T0A3<br>-----END PGP SIGNATURE-----
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