From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp12.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms5.migadu.com with LMTPS id +K2lDseF0WP5MAAAbAwnHQ (envelope-from ) for ; Wed, 25 Jan 2023 20:40:55 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp12.migadu.com with LMTPS id cMjHDseF0WPYFAAAauVa8A (envelope-from ) for ; Wed, 25 Jan 2023 20:40:55 +0100 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id C22F6A7FE for ; Wed, 25 Jan 2023 20:40:54 +0100 (CET) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pKld6-0004Yj-8D; Wed, 25 Jan 2023 14:40:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pKld3-0004YW-JU; Wed, 25 Jan 2023 14:40:17 -0500 Received: from server0.selfhosted.xyz ([217.64.149.7]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pKlcy-0001CD-56; Wed, 25 Jan 2023 14:40:15 -0500 Received: from server0.selfhosted.xyz (localhost [127.0.0.1]) by server0.selfhosted.xyz (Postfix) with ESMTP id 566D62E885EA; Wed, 25 Jan 2023 20:39:53 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=selfhosted.xyz; s=dkim; t=1674675599; bh=agjxN/YSVdDau8KymtgRuy1mBpC0eENM0gv/bTO9TRc=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=A4kSsPT8ruSOqVwZFOpqBc3TEcDk1rXDwuU3Rf5m/DoF9jp8LAJ6HhWuvxNY5MDCF DEez8nliFjsiOawCGMn5GaJoc9wS9HE6sB3ZE8mRM/tpjByt+ZzF8KOW2ZMY62zURy tq6fS4bEQns0OGRojn3al/oWuJ07IsH7d4PxuCy1xcZweggeUkMjNhJwgo3Ec2v2XJ Pb1iHEUEF1QMx0c0+/6/afjjTLvSLX0Q/JeE5tHsbps3rj1clbN9Omz3Gzdpl+6par QwDHJxDLGU6vuMnV+TRaNe24t0g08rAt70LyU+2zFlZpSnGx2rMQmzeXJaVMBX0duK mjXBOx0zUcLlQ== X-Fuglu-Suspect: bb277582088940c596ed7d9e05141ba5 X-Fuglu-Spamstatus: NO Received: from webmail.selfhosted.xyz (office.selfhosted.xyz [192.168.1.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: mail@selfhosted.xyz) by server0.selfhosted.xyz (Postfix) with ESMTPSA; Wed, 25 Jan 2023 20:39:53 +0100 (CET) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 25 Jan 2023 20:39:53 +0100 From: david larsson To: "(" Cc: guix-devel@gnu.org, guix-devel-bounces+david.larsson=selfhosted.xyz@gnu.org Subject: Re: Struggling to write Dissecting Guix, Part 2 In-Reply-To: References: Message-ID: X-Sender: david.larsson@selfhosted.xyz Received-SPF: pass client-ip=217.64.149.7; envelope-from=david.larsson@selfhosted.xyz; helo=server0.selfhosted.xyz X-Spam_score_int: -38 X-Spam_score: -3.9 X-Spam_bar: --- X-Spam_report: (-3.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FROM_SUSPICIOUS_NTLD=0.499, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_PDS_OTHER_BAD_TLD=0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: guix-devel-bounces+larch=yhetil.org@gnu.org X-Migadu-Country: US X-Migadu-Flow: FLOW_IN ARC-Seal: i=1; s=key1; d=yhetil.org; t=1674675655; a=rsa-sha256; cv=none; b=SKSOd8KyZ149S8CCwNDh3Vx4vRfnCnqTJiFjCQI6rcuIwjzflrD8bDbEYE/v+bZ0CpqBb3 PUxwdYNnclTRUvpPMLY+OY3sBmIVlfw2uwwSM+/x3jnmq7VrbilOJpqKwxG9J2UBV2Hd23 IAfmgU/A0MCCTpNHhkoigTiW88M1C2Ix+5vE4l/tZjdNiMaT4S9cqelS413U0mG3LPHnf2 rBvKhNYJ5Etu/SVMnCDa+Zrx2So8eukMHxTXVHKlt9xxqTgi5zF3FdWNTAg2B+AeYOLlXS CwgwrsSndODfdqEORG7a8JCdr/hNSeRLYtrQMA0Q2Icd4D4nWoYc9Yl4z/i3Pg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1674675655; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post:dkim-signature; bh=agjxN/YSVdDau8KymtgRuy1mBpC0eENM0gv/bTO9TRc=; b=mw8tTHDjvu+l/EoBK5qzoYTyix/bbCqqxidUxVxzDv4pY53EpzQItBMlm4TIIjkc55PYIF 7i6PM2kWBFUl9J2+bFpjThLwzfY8stfHR47GNCOPGNbOSlsFmcA1t8iIdqsR6/hg7xBtel VNkjT4vhkPiVBliphlge3spx1gMqURnMDz3NPpfbFUGxb2WPBEan6zHWhxqJo48Fh6J/U3 aEYi39xwVdBY4P7F+vacwLoAOK/b8gOqPpnfGsZj+8O5hG/5z6WZarja3pzzuAA5Lcn/gM b5p/q9mnZrAsQnNG4Z9Mz1Umg63dREAWs2ixPdH856Gw6JOBp0xSNfuQ/gFapw== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=selfhosted.xyz header.s=dkim header.b=A4kSsPT8; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org"; dmarc=pass (policy=none) header.from=selfhosted.xyz X-Migadu-Scanner: scn0.migadu.com X-Migadu-Spam-Score: -7.91 X-Spam-Score: -7.91 X-Migadu-Queue-Id: C22F6A7FE Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=selfhosted.xyz header.s=dkim header.b=A4kSsPT8; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org"; dmarc=pass (policy=none) header.from=selfhosted.xyz X-TUID: Mdu7BOFJyPJq On 2023-01-25 08:12, ( wrote: > Hello Guix, > > I've been struggling to write Part 2 of Dissecting Guix; I'm just not > sure where to start to > explain monads. > > It's hard for a variety of reasons, those being that: > > - Guile has no type system, so you can't express monads in terms of > types > - Guix doesn't implement very many monads (only state, identity, and > store), so it's > difficult to explain with a simpler monad, as there are no simpler > monads > - Guix doesn't have functors or monoids either, so it's hard to > "progressively" explain > first functors, then monoids, then monads > - Monads are just difficult in general :P > > Any suggestions? :/ > > -- ( Hi, Im not an expert on monads by any means, but... There's a monad tutorial fallacy to avoid: https://byorgey.wordpress.com/2009/01/12/abstraction-intuition-and-the-monad-tutorial-fallacy/ written by someone Brent: "Associate Professor of Computer Science at Hendrix College. Functional programmer, mathematician, teacher, pianist, follower of Jesus." And, personally, I liked this tutorial: https://towardsdatascience.com/monads-from-the-lens-of-imperative-programmer-af1ab8c8790c Maybe it helps, maybe not. Best regards, David