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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">In opam 2.0, it should definitely be possible to do it with a kind of dummy package which has a version constraint on the underlying OCaml package
holding the appropriate ocaml package below the next version (e.g. < 4.03.0 for the 4.02 channel – there might be a cleverer constraint than that even, IIRC). Each major version would correspond to a version of the package (say ocaml-branch.4.02 or something)
which you’d then pin at that version. A neat side-effect is that if a new maintenance release were made, the switch would be upgradable. It would also not require maintenance, beyond adding new major release versions.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">It’s not aliases, but would it do what you’re after? All of that’s impossible in OPAM 1.x – the best bet there would be to have an opam-admin script
which can process the compilers directory and re-generate the branch packages (something similar to Anil’s script for the GPRs).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">David<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">PS My strange patching work means I do keenly remember all point releases since 3.07 – who released 4.03.1 without telling me ;o)<o:p></o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></a></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"> opam-devel [mailto:opam-devel-bounces@lists.ocaml.org]
<b>On Behalf Of </b>Gabriel Scherer<br>
<b>Sent:</b> 30 December 2016 17:07<br>
<b>To:</b> opam-devel@lists.ocaml.org<br>
<b>Subject:</b> [opam-devel] Multiple names for the same switch (aliases that are really aliases)<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Hi opam-devel,<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">A few weeks ago I discussed with Jeremy Yallop the idea of having switches for major OCaml versions (4.01, 4.02, 4.03...) that would point to the currently-best minor version of them (do you remember? 4.01.0,
4.02.3, 4.03.1).<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">I would be willing to invest the effort of doing that and maintaining this mapping, but I feel that just creating new switches is too heavy-handed to be useful. If I already have a 4.02.3 switch, I would like
"opam switch 4.02" to bring me to that switch, not install a new, distinct one with name 4.02 that would in fact install the same compiler as 4.02.3.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Do I correctly understand that this feature is not possible in OPAM 1.2.x? (If it is, I may do it.)<br>
Is it possible in 2.x?<o:p></o:p></p>
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<p class="MsoNormal">(Louis: I do distinctly remember your call to try out 2.x at ICFP and I feel guilty about not having done much yet. Apologies.)<o:p></o:p></p>
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