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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US">Yes, we could<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;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> 18 August 2014 22:42<br>
<b>To:</b> ghc-devs<br>
<b>Subject:</b> The definition of cseProgram<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Currently, it's defined like this:<o:p></o:p></p>
<p>cseProgram :: CoreProgram -> CoreProgram<br>
cseProgram binds = cseBinds emptyCSEnv binds<o:p></o:p></p>
<p>cseBinds :: CSEnv -> [CoreBind] -> [CoreBind]<br>
cseBinds _ [] = []<br>
cseBinds env (b:bs) = (b':bs')<br>
where<br>
(env1, b') = cseBind env b<br>
bs' = cseBinds env1 bs<o:p></o:p></p>
<p>Couldn't we replace all that with the following? (Thanks to Cale for suggesting mapAccumL—I was using scanl because I knew it, but it was not a great fit.)<o:p></o:p></p>
<p>cseProgram = snd . mapAccumL cseBind emptyCSEnv<o:p></o:p></p>
<p>David Feuer<o:p></o:p></p>
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