From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37883) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d7SNZ-0004If-2P for guix-patches@gnu.org; Sun, 07 May 2017 16:02:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d7SNW-0005GH-1U for guix-patches@gnu.org; Sun, 07 May 2017 16:02:05 -0400 Received: from debbugs.gnu.org ([208.118.235.43]:34355) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1d7SNV-0005GA-Uh for guix-patches@gnu.org; Sun, 07 May 2017 16:02:01 -0400 Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1d7SNV-0003gh-Nd for guix-patches@gnu.org; Sun, 07 May 2017 16:02:01 -0400 Subject: bug#26339: [PATCH v3 1/9] system: Add extlinux support. Resent-Message-ID: References: <20170506154154.17836-1-m.othacehe@gmail.com> <20170506154154.17836-2-m.othacehe@gmail.com> <20170507184105.5897a5c8@scratchpost.org> From: Mathieu Othacehe In-reply-to: <20170507184105.5897a5c8@scratchpost.org> Date: Sun, 07 May 2017 22:01:27 +0200 Message-ID: <87bmr477xk.fsf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-patches-bounces+kyle=kyleam.com@gnu.org Sender: "Guix-patches" To: Danny Milosavljevic Cc: 26339@debbugs.gnu.org Hi Danny, > Not really - because I did this part already :) I'll remove it ;) >> + (if (and bootloader? bootloader) > > Hmm, is it possible to (usefully) check monadic values that way? Monads are still misterious for me, so I could be completely wrong here but I think that bootloader may be #f so it makes sense to check it here and in the following lines. > >> + (when (and bootloader? bootloader) > > Likewise. I wrote the few lines bellow to better understand what's going on : --8<---------------cut here---------------start------------->8--- (run-with-store (open-connection) (mlet* %store-monad ((test (return #f)) (disp -> (if test "true" "false"))) (return (display disp)))) --8<---------------cut here---------------end--------------->8--- You can ,expand it and make test return #t instead. Thanks, Mathieu