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<p class="MsoNormal"><span style="font-size:12.0pt">Colleagues<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">You will remember (see <a href="https://mail.haskell.org/pipermail/libraries/2015-February/024925.html">
this email</a>) that the Haskell community has been engaged in a debate about proposed changes to the Haskell Prelude, the
<a href="https://ghc.haskell.org/trac/ghc/wiki/Prelude710">Plan-List or Plan-FTP debate</a>.   We decided to hold an open survey to get feedback from the community.  Simon Marlow and Simon PJ were asked to make a decision in the light of that feedback.  The
 survey closed on 21 Feb, so it’s time to decide.<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:12.0pt">Bottom line: we recommend Plan FTP.<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size:12.0pt">There are strong arguments in both directions.  For the record, our own personal instincts were both in the conservative, Plan List direction.  But the survey gave some pretty compelling feedback, and was
 far more unequivocal than we expected.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Some details<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><b><span style="font-size:12.0pt">Over 800 people participated</span></b><span style="font-size:12.0pt"> in the survey. That’s a lot for an 11-day window. Many wrote several paragraphs of supporting information.  Thank you for
 participating so actively!<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><b><span style="font-size:12.0pt">Overall, 82% of respondents were in favour of FTP, a 4:1 majority</span></b><span style="font-size:12.0pt">.  Simon and I found this level of unanimity quite surprising – and it made our task
 much easier.  We clearly under-estimated the Haskell community’s appetite for absorbing change when they approve of the direction of travel.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><span style="font-size:12.0pt">Herbert helped us by doing a rough categorisation into hobbyist/non-hobbyist responses. 
<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:72.0pt;text-indent:-18.0pt;mso-list:l0 level2 lfo1">
<![if !supportLists]><span style="font-size:12.0pt;font-family:"Courier New""><span style="mso-list:Ignore">o<span style="font:7.0pt "Times New Roman"">  
</span></span></span><![endif]><span style="font-size:12.0pt">The first interesting fact is that there were a
<i>lot</i> of non-hobbyist responses: in fact a majority (58%) of the responses were from non-hobbyists.  So increasingly people are using Haskell for real work.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="margin-left:72.0pt;text-indent:-18.0pt;mso-list:l0 level2 lfo1">
<![if !supportLists]><span style="font-size:12.0pt;font-family:"Courier New""><span style="mso-list:Ignore">o<span style="font:7.0pt "Times New Roman"">  
</span></span></span><![endif]><span style="font-size:12.0pt">The support for Plan FTP among hobbyists was overwhelming (over 87%).  But it was still very strong indeed among non-hobbyists (over 79%).<o:p></o:p></span></p>
<p class="MsoListParagraph"><span style="font-size:12.0pt">Caveat: time was short, so the hobby/non-hobby categorisation is extremely approximate.  But since the results are so unambiguous, even the crude results are helpful.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l1 level1 lfo2"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><span style="font-size:12.0pt">We tried filtering out responses that were blank in the name field and both text boxes.  The 82% majority did not budge.<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:12.0pt">What happens now<o:p></o:p></span></b></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l1 level1 lfo2"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><b><span style="font-size:12.0pt">GHC 7.10 </span>
</b><span style="font-size:12.0pt">will embody Plan FTP. <b><o:p></o:p></b></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l1 level1 lfo2"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><b><span style="font-size:12.0pt">The Core Libraries committee</span></b><span style="font-size:12.0pt">, freshly energised and informed by this episode, is drafting new guidelines to clarify what it does, and how it works; and
 to help avoid a repetition of the recent drama.<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l1 level1 lfo2"><![if !supportLists]><span style="font-size:12.0pt;font-family:Symbol"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">      
</span></span></span><![endif]><b><span style="font-size:12.0pt">The responses.  </span>
</b><span style="font-size:12.0pt">In the survey we said “We won't publish either textual responses or personally-identifying information without your consent. The full responses will be made available only to a limited few.”   However, the English-language
 comments are a remarkable snapshot of the Haskell community, and it would be a shame to discard them without deeper study.  We propose to make them available to the Core Libraries Committee, to inform their future choices. 
<o:p></o:p></span></p>
<p class="MsoListParagraph"><span style="font-size:12.0pt">If anyone else wants to digest the comments into a summary report, we think that would be a service to the community, and (in our view, provided they are a reputable person etc) would fall under the
 “available to a limited few” rubric.  If that appeals to you, write to us.<o:p></o:p></span></p>
<p class="MsoListParagraph"><span style="font-size:12.0pt">If you object even to such limited sharing, write to us too.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">This wasn’t an entirely easy process, especially because it happened so late in the release cycle.  But although many people felt quite strongly about List vs FTP, the whole debate has involved light rather
 than heat; people have concentrated on the technical issues, rather than yelling.  Overall, it’s been very encouraging to see the resilience, transparency, and constructive tone of the community.  We really appreciate that – thank you. 
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Simon Marlow and Simon Peyton Jones<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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