<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin-top:6.0pt;
margin-right:0cm;
margin-bottom:6.0pt;
margin-left:0cm;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.Code, li.Code, div.Code
{mso-style-name:Code;
margin-top:0cm;
margin-right:0cm;
margin-bottom:0cm;
margin-left:22.7pt;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New";
mso-fareast-language:EN-US;
font-weight:bold;}
span.EmailStyle18
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
.MsoPapDefault
{mso-style-type:export-only;
margin-top:6.0pt;
margin-right:0cm;
margin-bottom:6.0pt;
margin-left:0cm;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-GB" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal">Dear friendly Cabal folk<o:p></o:p></p>
<p class="MsoNormal">Here’s what happened to me today<o:p></o:p></p>
<p class="Code">bash$ cabal install lhs2tex<o:p></o:p></p>
<p class="Code">cabal: Could not resolve dependencies:<o:p></o:p></p>
<p class="Code">[__0] next goal: report (user goal)<o:p></o:p></p>
<p class="Code">[__0] rejecting: report-0.1.0.0 (conflict: requires UnsaturatedTypeFamilies)<o:p></o:p></p>
<p class="Code">[__0] fail (backjumping, conflict set: report)<o:p></o:p></p>
<p class="Code">After searching the rest of the dependency tree exhaustively, these were the<o:p></o:p></p>
<p class="Code">goals I've had most trouble fulfilling: report<o:p></o:p></p>
<p class="MsoNormal">Crumbs. What is ‘report’? Why does it need UnsaturatedTypeFamilies? I’m totally lost.<o:p></o:p></p>
<p class="MsoNormal">Then, in an inspired moment, I thought to change to a different directory, ~/tmp.
<o:p></o:p></p>
<p class="MsoNormal">Then quite different things happened – it downloaded and built relevant libraries.<o:p></o:p></p>
<p class="MsoNormal">I think that there just happened to be a .cabal file in the original directory I was in at the time. That appears to affect what ‘cabal install’ does in a truly radical way.<o:p></o:p></p>
<p class="MsoNormal">My point is this: this is terribly confusing for the user (at least for this on). I’d be shocked if ‘apt install blah’ behaved utterly differently in different directories. I’m going to make a little empty directory somewhere, and cd
to it before invoking cabal in future. But that just feels like a workaround, not a solution.<o:p></o:p></p>
<p class="MsoNormal">I’m not saying it’s wrong – just giving you a data point that it had one user completely stumped<o:p></o:p></p>
<p class="MsoNormal">Simon<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="Code"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
</div>
</body>
</html>