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<p class="MsoNormal"><span style="font-family:"Calibri","sans-serif";mso-fareast-language:EN-US">Adding core-libraries, whose bailiwick this is.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri","sans-serif";mso-fareast-language:EN-US"><br>
Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri","sans-serif";mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif""> ghc-devs [mailto:ghc-devs-bounces@haskell.org]
<b>On Behalf Of </b>David Feuer<br>
<b>Sent:</b> 29 October 2014 00:24<br>
<b>To:</b> ghc-devs<br>
<b>Subject:</b> Is USE_REPORT_PRELUDE still useful?<o:p></o:p></span></p>
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A lot of code in GHC.List and perhaps elsewhere compiles differently depending on whether USE_REPORT_PRELUDE is defined. Not all code differing from the Prelude implementation. Furthermore, I don't know to what extent, if any, such code actually works these
days. Some of it certainly was not usable for *years* because GHC.List did not import GHC.Num. Should we<o:p></o:p></p>
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1. Convert all those code blocks to comments?<o:p></o:p></p>
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2. Go through everything, check it to make sure it's written as in the Prelude or has an alternative block, and then actually set up all the infrastructure so that works?<o:p></o:p></p>
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3. Leave it alone?<o:p></o:p></p>
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My general inclination is to go to 1.<o:p></o:p></p>
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<o:p> </o:p></p>
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I don't *really* like option 3 for four reasons:<o:p></o:p></p>
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a. It leaves untouched code to rot<o:p></o:p></p>
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b. It forces us to run CPP on files that otherwise have no need for it.<o:p></o:p></p>
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c. It interrupts the flow of the code with stuff that *looks* like real code (and is highlighted as such) but is actually inactive.<o:p></o:p></p>
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d. It's not hard to accidentally move code into or out of the #ifdef blocks.<o:p></o:p></p>
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