# variables Published articles for variables. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Six Heroku CLI Commands for Improving Terminal Workflows DevFeed: [Six Heroku CLI Commands for Improving Terminal Workflows]() Original publisher: [Read original article]() Author: Andy Smith Published: 2026-08-25T16:28:53Z Content type: tutorial Language: en Sources: [Heroku]() Topics: [Command-line interface](), [Heroku](), [Developer experience](), [code productivity]() Tags: [cli](), [command-line](), [commands](), [config](), [developer-experience](), [developer-tools](), [ecosystem](), [heroku](), [heroku-postgres](), [productivity](), [terminal](), [tools](), [variables]() ### AI overview This tutorial presents six Heroku CLI commands intended to reduce context switching and improve terminal-based workflows. The supplied content discusses exporting app configuration for local environments and checking active Heroku Postgres database queries, while warning about production configuration handling and credential leaks. ### Source excerpt Improving developer experience in the command line relies on minimizing context switches. While most engineers use the Heroku CLI strictly for basic tasks like pushing code, it contains a powerful suite of command line tools built to optimize your workflow. If you want to keep your focus locked on writing code, these six Heroku CLI commands will instantly upgrade your daily productivity. The post 6 Lesser-Known Heroku CLI Commands You Probably Aren't Using appeared first on Heroku. ## Design tokens: The building blocks of a design system DevFeed: [Design tokens: The building blocks of a design system]() Original publisher: [Read original article]() Published: 2026-08-18T00:00:00Z Content type: article Language: en Sources: [Aha! Engineering Blog]() Topics: [Design system](), [ui](), [CSS](), [consistency]() Tags: [atomic](), [component](), [css](), [design](), [design-system](), [source-of-truth](), [structure](), [tokens](), [ui](), [variables]() ### AI overview This article explains how design tokens provide a shared language for visual design attributes in a scalable design system. It contrasts tokens with hard-coded values, describes primitive and semantic tokens, and discusses using the Design Tokens Community Group standard to connect design and engineering. ### Source excerpt Implementing a design system at scale is often less about the pixels and more about the language we use to describe them. As a Senior Software Engineer at Aha! I've spent a lot of time thinking about how we can build a UI that is not only beautiful, ## Automatizar servidores con Ansible: primeros pasos DevFeed: [Automatizar servidores con Ansible: primeros pasos]() Original publisher: [Read original article]() Author: Antonio Pérez Published: 2026-01-08T00:00:00Z Content type: tutorial Language: es Sources: [tengoping.com]() Topics: [Ansible](), [Ansible Roles](), [ssh](), [dry-run](), [Git](), [nginx]() Tags: [ansible](), [dry-run](), [git](), [nginx](), [ssh](), [sysadmins](), [variables](), [vault]() ### AI overview A step-by-step introduction to automating server configuration with Ansible. It covers ad-hoc commands, inventories, playbooks, dry runs, roles, group variables, loops, and secrets with ansible-vault. ### Source excerpt Ansible desde cero: comandos ad-hoc, playbooks, roles, variables por grupo, bucles y secretos con ansible-vault, paso a paso. ## Year in Review: 2024 DevFeed: [Year in Review: 2024]() Original publisher: [Read original article]() Author: hello@taniarascia.com Published: 2025-03-27T00:00:00Z Content type: article Language: en Sources: [Tania Rascia]() Topics: [coding](), [CSS](), [React](), [Web Development](), [Web platform]() Tags: [bluesky](), [burnout](), [career](), [coding](), [css](), [hooks](), [keyboard](), [meta](), [pagination](), [projects](), [react](), [redesign](), [review](), [side-projects](), [sorting](), [table](), [variables](), [year-in-review]() ### AI overview A 2024 year-in-review from a principal engineer who continues to work primarily with React and CSS. The author reflects on balancing a full-time engineering role with coding, writing, side projects, and maintaining a personal website, while highlighting several articles and a blog redesign completed during the year. ### Source excerpt I'm trying to win the award for "Latest Year in Review". 🏆 I don't know if anyone can challenge me at this point, as it's almost thirdway... ## Going Global with Twig Globals in Craft CMS DevFeed: [Going Global with Twig Globals in Craft CMS]() Original publisher: [Read original article]() Author: andrew@nystudio107.com (Andrew Welch) Published: 2024-09-02T18:25:00Z Content type: tutorial Language: en Sources: [nystudio107 | Articles on modern web development.]() Topics: [Content Management System](), [Web](), [coding]() Tags: [added](), [article](), [challenges](), [cms](), [collection](), [craft](), [global](), [globals](), [how-to](), [insights](), [learn](), [leveraging](), [simplify](), [templating](), [twig](), [variables]() ### AI overview This tutorial explains how variable scope works in Twig templates used by Craft CMS, including the challenges of making variables globally available. It discusses the trade-offs of global variables and how they can reduce component reusability and modularity, while noting that they can be appropriate in simpler websites. ### Source excerpt Learn how to simplify some Twig templating challenges by leveraging the global variables & the _globals Collection added in Craft CMS 4.5 ## CSS @property and browser support for custom properties DevFeed: [CSS @property and browser support for custom properties]() Original publisher: [Read original article]() Published: 2024-07-12T00:00:00Z Content type: article Language: en Sources: [Una Kravets]() Topics: [CSS](), [Web Development](), [browser]() Tags: [browser](), [css](), [development](), [property](), [variables](), [web-development]() ### AI overview This article discusses the CSS @property feature, describing it as a way to use CSS variables with broad browser support. ### Source excerpt The CSS Anchor Positioning API is a game-changer in web development because it lets you natively position elements. ## Time-travel debugging production code DevFeed: [Time-travel debugging production code]() Original publisher: [Read original article]() Author: Loren Sands-Ramshaw Published: 2023-08-07T15:00:00Z Content type: tutorial Language: en Sources: [Temporal Blog]() Topics: [debugging](), [debug](), [Code](), [Tooling]() Tags: [breakpoint](), [code](), [debugging](), [history](), [implementation](), [state](), [temporal-concepts](), [time-travel-debugging](), [variables]() ### AI overview This post explains time-travel debugging, also known as reverse debugging, and how it lets developers inspect past program states by stepping backward through execution. It covers the technique's history, examples across languages and development environments, and three implementation approaches, including record and replay. ### Source excerpt Learn how time-travel debuggers, including Temporal, can help you rewind and debug past executions to resolve complex issues efficiently. ## Dark Theme - CSS Migration DevFeed: [Dark Theme - CSS Migration]() Original publisher: [Read original article]() Author: Zaid Daba'een Published: 2023-07-06T11:19:48Z Content type: tutorial Language: en Sources: [DeveloperHub.io]() Topics: [Dark Mode](), [CSS](), [modern web development](), [developer tooling]() Tags: [branding](), [css](), [dark-mode](), [devtools](), [migration](), [variables]() ### AI overview This tutorial explains DeveloperHub's new dark theme, including how to enable it, add a reader theme toggle, test it with DevTools, migrate custom CSS, and customize colors with CSS variables. ### Source excerpt Dark theme is out now! Let those eyes rest. ## Map as a property delegate DevFeed: [Map as a property delegate]() Original publisher: [Read original article]() Published: 2023-05-08T00:15:00Z Content type: tutorial Language: en Sources: [Kt. Academy]() Topics: [Kotlin](), [properties](), [interface](), [object]() Tags: [function](), [interface](), [kotlin](), [maps](), [property](), [standard-library](), [state](), [variables](), [workshop-learning-programming]() ### AI overview A Kotlin tutorial explains how Map can act as a read-only property delegate, including use cases for objects with known and dynamically added properties. It also explains variable assignment and shared mutable-object behavior through a community puzzle. ### Source excerpt How do we use Map as a property delegate, and why the result of a famous puzzler should not be surprising. ## LATERAL is Your Friend to Create Local Column Variables in SQL DevFeed: [LATERAL is Your Friend to Create Local Column Variables in SQL]() Original publisher: [Read original article]() Author: lukaseder Published: 2022-11-04T08:56:17Z Content type: tutorial Language: en Sources: [jOOQ]() Topics: [SQL](), [Databases]() Tags: [apply](), [cross-apply](), [cross-join-lateral](), [derived-table](), [examples](), [lateral](), [lateral-derived-table](), [local-variables](), [oracle](), [outer-apply](), [postgresql](), [sql](), [sql-server](), [variables]() ### AI overview This article explains how SQL's LATERAL clause can be used to define local column variables next to the tables that provide their values. It compares this approach with derived tables and notes database-specific syntax, including SQL Server's CROSS APPLY. ### Source excerpt The standard SQL WITH clause has been tremendously helpful in structuring SQL queries. Instead of nesting everything in unreadable derived tables like this: People have started moving the logic up front, just like in any other programming language, where we declare things first, lexically, then use them: Both queries will produce the 5 actors with ... Continue reading LATERAL is Your Friend to Create Local Column Variables in SQL -> ## Performance in Jetpack Compose DevFeed: [Performance in Jetpack Compose]() Original publisher: [Read original article]() Author: Denys Rudenko Published: 2022-10-03T16:41:03Z Content type: tutorial Language: en Sources: [Stories by Denis Rudenko on Medium]() Topics: [Jetpack Compose](), [ui](), [Code]() Tags: [android](), [android-app-development](), [article](), [compiler](), [compose](), [false-positive](), [jetpack-compose](), [lambda](), [modifiers](), [performance](), [recomposition](), [scopes](), [skip](), [ui](), [val](), [var](), [variables]() ### AI overview A practical guide to improving Jetpack Compose performance through stable parameters, skippable composables, optimized recompositions, remembered lambdas, and compiler and layout-inspector metrics. ### Source excerpt Article tells about my research on how to write efficient Compose code. It consists of 6 sections and a TL;DR/Summary in the end. We will cover: Optimising recompositions When should you use @Immutable and @Stable annotations; Unstable classes, variables, lambdas; Non-restartable & skippable composables; Lambda modifiers; Passing lambdas providing required fields instead of fields in composables; Inlined composables; When you should use remember { }. We'll be using Compose Compiler Metrics and layout inspector tools to know: - If a class is stable or not; - If the composable function is skippable/restartable; - Amount of skipped recompositions. 1. Unstable objects on UI layer. To understand why we should care about stability, let us peek into a very important metric called skippability. It allows compose runtime to skip recomposition of a composable when all the parameters it uses are considered stable. What is considered stable by the compiler? - All primitive value types: Boolean, Int, Long, Float, Char, etc. - Strings - Lambdas (not always, we will get to it later) We want composable functions to use stable params to become skippable. 1) Don't use var when seeking stability. Fields declared as var are considered unstable: https://medium.com/media/724da23ba38eaa9d3312318e7e8038b9/hrefhttps://medium.com/media/f8dd8a39bce60e48b5ff8bdd4a02b9ef/href UserDetails composable will be recomposed even if the user never gets modified. Using val instead of var in User class will fix this issue. 2) Not all lambdas are considered stable. Let's look at the following examples: https://medium.com/media/fbbff417d165a501b21a3e5d2c6f087f/hrefhttps://medium.com/media/c6aaae01fda67c633edcdf7bb351e620/href Since the lambdas capture outside scopes, they won't be automatically inferred as stable and reused as expected. If the lambda requires access to external variables, the compiler will add those variables as fields, which are passed into the constructor of the lambda. We go a 2 ways of ## Variables point to objects DevFeed: [Variables point to objects]() Original publisher: [Read original article]() Published: 2021-11-17T00:00:00Z Content type: tutorial Language: en Sources: [Kt. Academy]() Topics: [Variable](), [object](), [Kotlin](), [Code]() Tags: [code](), [exception](), [kotlin](), [object](), [variable](), [variables](), [workshop-learning-programming]() ### AI overview A tutorial explaining how variables reference objects, how reassignment differs from mutating an object, and how these distinctions apply to mutable and read-only Kotlin lists and delegated properties backed by maps. ### Source excerpt A basic feature, that is commonly misunderstood. ## Using GoReleaser includes feature DevFeed: [Using GoReleaser includes feature]() Original publisher: [Read original article]() Author: Carlos Alexandro Becker Published: 2021-07-03T00:00:00Z Content type: tutorial Language: en Sources: [Carlos Becker]() Topics: [configuration](), [Template](), [GitHub Actions](), [Script](), [deprecated]() Tags: [config](), [deprecated](), [files](), [github-actions](), [include](), [modular](), [scripts](), [using](), [variables](), [workflow]() ### AI overview This tutorial explains how to use GoReleaser Pro's includes feature to share full or partial configuration files across projects. It describes a modular repository of reusable configuration files, custom template variables, recursive imports, and a GitHub Actions workflow that detects deprecated or invalid settings. ### Source excerpt GoReleaser Pro was released about a month ago, and with it, the ability to include GoReleaser config files. ## The Houdini Properties and Values API is coming to CSS in Chromium 85 DevFeed: [The Houdini Properties and Values API is coming to CSS in Chromium 85]() Original publisher: [Read original article]() Published: 2020-07-21T00:00:00Z Content type: release Language: en Sources: [Una Kravets]() Topics: [CSS](), [API](), [Chromium](), [properties]() Tags: [api](), [chromium](), [css](), [properties](), [property](), [variables]() ### AI overview The article covers the arrival of the Houdini Properties and Values API in CSS with Chromium 85. ### Source excerpt The Houdini Properties and Values API is coming to your CSS file in Chromium 85. ## Let's Build A Simple Interpreter. Part 19: Nested Procedure Calls DevFeed: [Let's Build A Simple Interpreter. Part 19: Nested Procedure Calls]() Original publisher: [Read original article]() Author: Ruslan Spivak Published: 2020-03-19T12:45:00Z Content type: tutorial Language: en Sources: [Ruslan Spivak]() Topics: [Code](), [file]() Tags: [blog](), [code](), [github](), [parameter](), [program](), [scope](), [scopes](), [variable](), [variables]() ### AI overview This tutorial explains how to execute nested procedure calls in a simple interpreter. It demonstrates nested procedures Alpha and Beta, examines their activation records, and fixes the nesting level for Beta by using the scope level stored in the scoped symbol table. ### Source excerpt What I cannot create, I do not understand. --- Richard Feynman ## Using Rust Playground for Hello World and Variable Interpolation DevFeed: [Using Rust Playground for Hello World and Variable Interpolation]() Original publisher: [Read original article]() Author: Fuzzygroup Published: 2020-03-02T00:00:00Z Content type: tutorial Language: en Sources: [Scott Johnson]() Topics: [Rust](), [Code](), [compiled language](), [Repl.it](), [browser]() Tags: [browser](), [code](), [compiled-language](), [experiment](), [function](), [immutability](), [language](), [let](), [playground](), [program](), [run](), [rust](), [variables]() ### AI overview A beginner-oriented walkthrough of using Rust Playground to run a Hello World program and experiment with variables. It explains Rust syntax such as fn, println!, let, and string interpolation, and briefly compares Rust Playground with Repl.it, including a criticism of Repl.it's paid privacy option. ### Source excerpt Artwork by my friend Autumn Mott; Hopefully I can find a better link to put here It is a Monday and what better way to start your 6 am Monday morning then learning some of the elements of a new language - Rust. I started by adding a link in my Browser toolbar to the Rust Playground which amounts to a web based REPL (Read Evaluate Print Loop) for Rust where you can type in Rust code and run it. Yes I know it really isn't a REPL because Rust is a compiled language not an interpreted one but it functions well enough as a REPL that I can wrap my Ruby tinged mind around it. Here's the Hello World program that automatically appears in the Rust playground fn main() { println!("Hello, world!"); } The output of this is: Hello, world! That's pretty easy to understand: A main function defined with fn A print line function defined with a ! (my previous Rust reading tells me that's a macro indicator) { and } to denote structure A ; to denote the end of lines I wanted to make a simple change to experiment with the use of variables so I added a main2() function and called it from main(): fn main() { println!("Hello, world!"); main2(); } fn main2() { let x = 5; println!("The value of x is: {}", x); let y = 6; println!("The value of y is: {}", y); } The output of this is: Hello, world! The value of x is: 5 The value of y is: 6 You can see that the let keyword assigns a variable and that {} binds a variable into a string (which is generally called interpolation). Note: Variables quickly bring you in to the heart of Rust - immutability - and here there by dragons that hopefully come up tomorrow after some reading. Link Here's a permanent link to this if you want to try it out. What about Repl.it? Another way to have a web based REPL for Rust is Repl.it. And while I like the concept of repl.it, they have eliminated any privacy without a paid account: Upgrade your account for private repls. This appears on the bottom of every new REPL you create and at $74 / 12 months that feels expensi ## Flat Multi-Environment Config for Craft CMS 3 DevFeed: [Flat Multi-Environment Config for Craft CMS 3]() Original publisher: [Read original article]() Author: andrew@nystudio107.com (Andrew Welch) Published: 2020-02-29T15:29:00Z Content type: tutorial Language: en Sources: [nystudio107 | Articles on modern web development.]() Topics: [Content Management System](), [.env](), [Environment Variables](), [configuration](), [Development]() Tags: [aliases](), [api-keys](), [approach](), [article](), [cms](), [config](), [configs](), [craft](), [database](), [docker](), [environment](), [environment-variables](), [file](), [files](), [flat](), [git](), [heroku](), [insights](), [multi-environment](), [need](), [presents](), [secrets](), [sorts](), [variables]() ### AI overview A tutorial on configuring Craft CMS 3 across development, staging, and production environments using aliases, environment variables, .env files, and configuration files. It presents a flat configuration approach and discusses keeping environment-specific credentials and secrets separate from source code and databases. ### Source excerpt Multi-environment configs for Craft CMS are a mix of aliases, environment variables, and config files. This article sorts it all out, and presents a flat config file approach ## Let's Build A Simple Interpreter. Part 18: Executing Procedure Calls DevFeed: [Let's Build A Simple Interpreter. Part 18: Executing Procedure Calls]() Original publisher: [Read original article]() Author: Ruslan Spivak Published: 2020-02-20T13:00:00Z Content type: tutorial Language: en Sources: [Ruslan Spivak]() Topics: [Code](), [function](), [Algorithm]() Tags: [algorithm](), [blog](), [code](), [constructor](), [create](), [function](), [local-variables](), [object](), [parameter](), [program](), [variables]() ### AI overview This tutorial extends an interpreter to execute procedure calls. It focuses on procedures that access parameters and local variables, explaining activation records, call-stack handling, procedure execution, and the implementation of the visit_ProcedureCall method. ### Source excerpt Do the best you can until you know better. Then when you know better, do better. ― Maya Angelou ## Locally Scoped CSS Variables: What, How, and Why DevFeed: [Locally Scoped CSS Variables: What, How, and Why]() Original publisher: [Read original article]() Published: 2017-06-05T00:00:00Z Content type: tutorial Language: en Sources: [Una Kravets]() Topics: [CSS](), [modern web development](), [JavaScript]() Tags: [css](), [javascript](), [processors](), [properties](), [scope](), [variables]() ### AI overview This article explains CSS custom properties, including how their dynamic values differ from variables compiled by Sass and PostCSS. It covers local scope, JavaScript integration, partial values within properties, and using variables to create cleaner component styles. ### Source excerpt Leveraging CSS Variable scope improves the size, specificity, and semantics of our stylesheets. This article talks all about what CSS Variables are and how we can leverage scope to improve our styling. ## Testing Polynomial Equality DevFeed: [Testing Polynomial Equality]() Original publisher: [Read original article]() Published: 2017-04-24T09:00:14Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Testing](), [function]() Tags: [field](), [function](), [polynomials](), [random](), [roots](), [testing](), [variables]() ### AI overview The article explains how to test whether two multivariable polynomial expressions represent the same function. It presents randomized evaluation over a finite subset of a field and uses the Schwartz-Zippel lemma to bound the probability of an incorrect equality judgment. ### Source excerpt Problem: Determine if two polynomial expressions represent the same function. Specifically, if $ p(x_1, x_2, \dots, x_n)$ and $ q(x_1, x_2, \dots, x_n)$ are a polynomial with inputs, outputs and coefficients in a field $ F$, where $ |F|$ is sufficiently large, then the problem is to determine if $ p(\mathbf{x}) = q(\mathbf{x})$ for every $ x \in F$, in time polynomial in the number of bits required to write down $ p$ and $ q$. ## Let's Build A Simple Interpreter. Part 10. DevFeed: [Let's Build A Simple Interpreter. Part 10.]() Original publisher: [Read original article]() Author: Ruslan Spivak Published: 2016-08-04T13:15:00Z Content type: tutorial Language: en Sources: [Ruslan Spivak]() Topics: [Programming](), [Programming language](), [Code](), [Compiler]() Tags: [article](), [blog](), [build](), [code](), [command-line](), [compiler](), [example](), [github](), [programming-language](), [simple](), [types](), [variable](), [variables]() ### AI overview This tutorial continues a series on building a Pascal interpreter. It updates the interpreter to parse and interpret a complete Pascal program, covering program headers, variable declarations, integer and floating-point division, comments, and grammar changes. ### Source excerpt Today we will continue closing the gap between where we are right now and where we want to be: a fully functional interpreter for a subset of Pascal programming language. In this article we will update our interpreter to parse and interpret our very first complete Pascal program. The program ... ## Zero Knowledge Proofs for NP DevFeed: [Zero Knowledge Proofs for NP]() Original publisher: [Read original article]() Published: 2016-08-01T08:00:53Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Zero-knowledge proof](), [zero-knowledge](), [Cryptography](), [Algorithms](), [Code]() Tags: [algorithm](), [boolean](), [circuit](), [computational-complexity](), [cryptography](), [graph-isomorphism](), [interactive](), [mathematics](), [np](), [np-hard](), [one-way-functions](), [programming](), [python](), [random-number-generators](), [variables](), [zero-knowledge]() ### AI overview This tutorial explains how zero-knowledge proofs extend beyond graph isomorphism to problems in NP, using cryptography to let a prover convince a verifier without revealing the secret knowledge behind the claim. It introduces examples including boolean formulas, subset sums, graph 3-coloring, and boolean circuits, and describes an implementation of a proof for graph 3-colorability. ### Source excerpt Last time, we saw a specific zero-knowledge proof for graph isomorphism. This introduced us to the concept of an interactive proof, where you have a prover and a verifier sending messages back and forth, and the prover is trying to prove a specific claim to the verifier. A zero-knowledge proof is a special kind of interactive proof in which the prover has some secret piece of knowledge that makes it very easy to verify a disputed claim is true. ## Classy CSS: a Programmatic Approach to Sass Stylesheets DevFeed: [Classy CSS: a Programmatic Approach to Sass Stylesheets]() Original publisher: [Read original article]() Published: 2015-11-15T00:00:00Z Content type: opinion Language: en Sources: [Una Kravets]() Topics: [CSS](), [Sass](), [modern web development](), [Front end]() Tags: [architecture](), [components](), [css](), [libraries](), [modular](), [properties](), [sass](), [variables]() ### AI overview An opinionated article introduces Classy CSS, a programmatic, modular, scalable, and class-based architecture for Sass stylesheets. It explains the approach through a button example and discusses its relationship to BEM-like naming and Sass features. ### Source excerpt An opinionated Sass architecture system for writing modular and scalable libraries. Also, a case in defense of extends. ## I wrote Antigen in Go: Antibody DevFeed: [I wrote Antigen in Go: Antibody]() Original publisher: [Read original article]() Author: Carlos Alexandro Becker Published: 2015-06-06T00:00:00Z Content type: opinion Language: en Sources: [Carlos Becker]() Topics: [Go Language](), [Haskell](), [Erlang]() Tags: [code](), [concurrently](), [erlang](), [execution](), [go](), [language](), [learning](), [post](), [thoughts](), [variables]() ### AI overview A personal account of learning Go while building Antibody, a reimplementation of Antigen. The article discusses Go's syntax, built-in formatting and error checks, and its concurrency features for processing plugin bundles. ### Source excerpt Learning Go was in my TODO list for a while, and finally I did something about it. This post contains some thoughts about it... [Next page]()