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Programming Leftovers

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  • Russ Allbery: faq2html 1.36

    faq2html is the program I use to turn various text files into web pages.

  • CMake Script Mode

    There’s a Dutch phrase, voortschrijdend inzicht, which can be used to describe new insights and continuous improvement in something. In social media terms, perhaps TIL comes close. Let’s talk about an under-illuminated, yet useful CMake feature. Script mode!


    It turns out project() isn’t a CMake command that you can use in script mode. But you can set variables, so I introduced a CALAMARES_VERSION variable, set to the current release. Years ago I already had such a variable, but then moved the version-setting to project when CMake 3.0 became a requirement. So voortschrijdend inzicht can also go in a circle!

    When CMake runs in script mode, the variable CMAKE_SCRIPT_MODE_FILE is set; outside of script mode, it isn’t (unless you’re messing with the cache or command-line arguments, in which case you should be ashamed of yourself).

    In script mode, CMAKE_SOURCE_DIR is set to the current directory, not the directory with the top-level CMakeLists.txt file (naturally: there’s no generation or build going on, so there need not be such a file!). I wrestled Teo Mrnjavac’s original date-and-git-stamping CMake code (written for Calamares in 2015, for CMake 2.8) into a function and stuffed it into a separate file. It takes a version string and extends it, placing the output value into a variable.

  • In defence of OOP

    During the last years it became fashionable to rag on object oriented programming and a decade ago I would join the choir. Hack, when I started with Perl I despised the bloat and inefficiency of many corporate smelling *coughjava* systems and preached the light weight and foreward thinking way that real hackers travel. In this miniseries I want to write why I changed my tune [part one], the best way (IMO) to use OOP [part two] and why inheritance (incl. roles and templates) and delegation or not helpful features (in contrast to polymorphism) [part three]. Maybe there will be more about rating Perl OO features and modules.

    Objects are a tool to create abstraction layer - to do anything. It's easy to get overwhelmed by possibilities or run with preconceived ideas. And the larger the system, the harder it is to make wise choices. I think this is one reason why a lot of OO code sucks. The second is bad coding styles it's not getting taught enough how to find the right abstractions and how to ease the use by proper naming. The third reason is the introduction and teaching of contra-productive features like inheritance and even worse, multiple inheritance.


    Once you get a lot of subs, you prevent name collisions with name spaces (packages), that also give you order so that each sub is in the right place in the hierarchy. But when the namespaces get nested and names becoming longer you start to which for classes, so you can call the method directly on the object - but were not there yet. Also, attribute data is sanitized once, when coming via a setter into the object and can be used over and over without any second check. So you can pass the object into a sub and data can be used without check. This advantage would vanish if you could reach into object internals - but still this is not my main two points.

    With the ability to capsule data you can guarantee to oblige to contracts. (I already touched on that.). Most importantly strict abstraction layer walls will tell you if your abstraction layers are appropriate. You will notice it if there is a need to violate them or if your classes or methods get to big. This are clear signs that code has to be refactored. And if you have to many classes, it is a sign you don't have enough high order classes. OOP can be used in a very functional manner which is often less painful (in larger projects) than being strictly functional and fighting with monads all the time. But how exactly do that will be content of the next part ....

  • Arm Neoverse V1 Tuning Lands In GCC 11 Compiler

    In addition to AMD Zen 3 "znver3" seeing a lot of last minute tuning/optimization work ahead of the GCC 11 compiler being released as stable in the weeks ahead, Arm has also been getting some last minute work into this open-source compiler as it pertains to the Neoverse V1 support.

More in Tux Machines

digiKam 7.7.0 is released

After three months of active maintenance and another bug triage, the digiKam team is proud to present version 7.7.0 of its open source digital photo manager. See below the list of most important features coming with this release. Read more

Dilution and Misuse of the "Linux" Brand

Samsung, Red Hat to Work on Linux Drivers for Future Tech

The metaverse is expected to uproot system design as we know it, and Samsung is one of many hardware vendors re-imagining data center infrastructure in preparation for a parallel 3D world. Samsung is working on new memory technologies that provide faster bandwidth inside hardware for data to travel between CPUs, storage and other computing resources. The company also announced it was partnering with Red Hat to ensure these technologies have Linux compatibility. Read more

today's howtos

  • How to install go1.19beta on Ubuntu 22.04 – NextGenTips

    In this tutorial, we are going to explore how to install go on Ubuntu 22.04 Golang is an open-source programming language that is easy to learn and use. It is built-in concurrency and has a robust standard library. It is reliable, builds fast, and efficient software that scales fast. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel-type systems enable flexible and modular program constructions. Go compiles quickly to machine code and has the convenience of garbage collection and the power of run-time reflection. In this guide, we are going to learn how to install golang 1.19beta on Ubuntu 22.04. Go 1.19beta1 is not yet released. There is so much work in progress with all the documentation.

  • molecule test: failed to connect to bus in systemd container - openQA bites

    Ansible Molecule is a project to help you test your ansible roles. I’m using molecule for automatically testing the ansible roles of geekoops.

  • How To Install MongoDB on AlmaLinux 9 - idroot

    In this tutorial, we will show you how to install MongoDB on AlmaLinux 9. For those of you who didn’t know, MongoDB is a high-performance, highly scalable document-oriented NoSQL database. Unlike in SQL databases where data is stored in rows and columns inside tables, in MongoDB, data is structured in JSON-like format inside records which are referred to as documents. The open-source attribute of MongoDB as a database software makes it an ideal candidate for almost any database-related project. This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of the MongoDB NoSQL database on AlmaLinux 9. You can follow the same instructions for CentOS and Rocky Linux.

  • An introduction (and how-to) to Plugin Loader for the Steam Deck. - Invidious
  • Self-host a Ghost Blog With Traefik

    Ghost is a very popular open-source content management system. Started as an alternative to WordPress and it went on to become an alternative to Substack by focusing on membership and newsletter. The creators of Ghost offer managed Pro hosting but it may not fit everyone's budget. Alternatively, you can self-host it on your own cloud servers. On Linux handbook, we already have a guide on deploying Ghost with Docker in a reverse proxy setup. Instead of Ngnix reverse proxy, you can also use another software called Traefik with Docker. It is a popular open-source cloud-native application proxy, API Gateway, Edge-router, and more. I use Traefik to secure my websites using an SSL certificate obtained from Let's Encrypt. Once deployed, Traefik can automatically manage your certificates and their renewals. In this tutorial, I'll share the necessary steps for deploying a Ghost blog with Docker and Traefik.