Category

Programming Tutorials and Coding Guides

Explore programming tutorials with practical examples across multiple languages, scripting, and development concepts for beginners and advanced users.

Welcome to the Programming tutorials section, where you will learn coding concepts with real-world examples across multiple languages and platforms.

This category includes beginner to advanced guides covering scripting, automation, and application development in Java, JavaScript, Python, Go, TypeScript, and related stacks.

Whether you are learning programming for system administration or building applications, browse the articles below for practical examples and language-specific references.

Programming plays a crucial role in modern infrastructure and DevOps workflows. You can also explore DevOps and Linux to see how code integrates with system-level operations.

956 articles

Programming category illustration with code editor, automation, and debugging graphics
programming

JavaScript scrollTo(): Scroll Window or Element Position

Learn JavaScript scrollTo() with window.scrollTo(), smooth scrolling, scroll to element, scrollIntoView(), and scroll position examples.

Olorunfemi Akinlua2 min read
programming

JavaScript YAML Parser: Parse YAML in Node.js

Learn how to parse YAML in JavaScript and Node.js with yaml and js-yaml, read YAML files, convert YAML to JSON, and handle parser errors safely.

Olorunfemi Akinlua4 min read
programming

JavaScript return vs throw: When to Return Errors or Throw

Understand return vs throw in JavaScript, when to return error values, when to throw errors, and how try...catch handles exceptions.

Olorunfemi Akinlua3 min read
programming

JavaScript JSON.parse(): Parse JSON Strings, Objects, and Files

JSON.parse in JavaScript: valid JSON strings, SyntaxError on bad input, reviver functions, and safe parsing habits.

Olorunfemi Akinlua2 min read
programming

Factorial Function in JavaScript Using Recursion

Learn how to write a factorial function in JavaScript using recursion, base cases, input validation, and an iterative alternative.

Olorunfemi Akinlua3 min read
programming

JavaScript Recursive Map Object: Transform Nested Values

Learn how to recursively map over a JavaScript object, transform nested values, preserve arrays, and create a new object without mutating input data.

Olorunfemi Akinlua3 min read
programming

JavaScript Recursive Search in Array of Objects

Learn how to recursively search an array of objects in JavaScript, find nested objects by ID, return all matches, and search child arrays safely.

Olorunfemi Akinlua3 min read
programming

JavaScript Recursive Generator with yield* Examples

Learn JavaScript recursive generators with function*, yield, yield*, tree traversal, converting generators to arrays, and practical examples.

Olorunfemi Akinlua3 min read
programming

JavaScript Pattern Matching with RegExp Examples

Learn JavaScript pattern matching with regular expressions using search(), match(), matchAll(), replace(), split(), and the RegExp constructor.

Olorunfemi Akinlua4 min read
programming

JavaScript Optional Parameters and Default Values

JavaScript optional parameters: default parameters, undefined vs null, options objects, destructuring defaults, and arguments.length patterns.

Olorunfemi Akinlua2 min read
programming

JavaScript Promise.reject(): Create and Handle Rejected Promises

Learn Promise.reject() in JavaScript with catch(), async/await, error handling, Promise.resolve comparison, and tested rejection examples.

Olorunfemi Akinlua3 min read
programming

JavaScript Promise.resolve(): Create Resolved Promises

Learn Promise.resolve() in JavaScript with resolved values, existing promises, thenables, async functions, and Promise.reject comparison.

Olorunfemi Akinlua3 min read
programming

JavaScript Promise.race (first settled promise)

JavaScript Promise.race explained: first settled promise wins, timeout patterns, empty iterable, non-Promise inputs, and how it differs from Promise.all and Promise.any. Every sample output was run on Node.js (V8).

Olorunfemi Akinlua4 min read
programming

JavaScript Set add(): Add Values to a Set

Learn JavaScript Set add() with examples showing unique values, chaining, object references, has(), size, and converting a Set to an array.

Olorunfemi Akinlua2 min read
programming

JavaScript NodeList: querySelectorAll, forEach, and Array.from

Learn JavaScript NodeList with practical examples. Understand NodeList vs Array, NodeListOf, querySelectorAll, forEach, Array.from, static NodeList behavior, and NodeList vs HTMLCollection.

Olorunfemi Akinlua2 min read
programming

JavaScript querySelector(): Select DOM Elements with CSS Selectors

Learn JavaScript querySelector() with CSS selectors, document.querySelector(), querySelectorAll(), null checks, selector errors, and practical DOM examples.

Olorunfemi Akinlua3 min read
programming

JavaScript parseFloat(): Convert Strings to Decimal Numbers

Learn how JavaScript parseFloat() converts strings to decimal numbers, how it handles trailing characters, NaN, scientific notation, and how it differs from Number().

Olorunfemi Akinlua3 min read
programming

JavaScript startsWith(): Check if a String Starts With Text

Learn JavaScript startsWith() with examples for checking string prefixes, using the position argument, case sensitivity, and alternatives.

Olorunfemi Akinlua2 min read
programming

JavaScript String Contains: includes(), indexOf(), and Regex

Learn how to check if a JavaScript string contains a substring using includes(), indexOf(), regular expressions, position checks, and case-insensitive search.

Steve Alila2 min read
programming

JavaScript Print Object: console.log and JSON.stringify Examples

Learn how to print objects in JavaScript using console.log(), JSON.stringify(), console.table(), Object.keys(), Object.values(), and object entries.

Olorunfemi Akinlua3 min read
programming

JavaScript Redirect to URL with location.href, assign, and replace

Learn JavaScript redirect methods using window.location.href, location.assign(), location.replace(), relative URLs, and redirect behavior in browser history.

Steve Alila3 min read
programming

JavaScript slice(): Array and String Examples

Learn JavaScript slice() for arrays and strings, including start/end indexes, negative indexes, shallow copy behavior, and slice vs splice.

Olorunfemi Akinlua2 min read
programming

JavaScript Send Tab Key and Detect Tab Key Press

Learn how to detect the Tab key in JavaScript, understand keyCode 9, handle KeyboardEvent.key, and why browsers restrict simulated Tab navigation.

Olorunfemi Akinlua2 min read
programming

JavaScript Sort by Date: Ascending and Descending Examples

Learn how to sort dates in JavaScript using Array.sort(), Date objects, timestamps, ascending and descending order, and safe ISO date strings.

Olorunfemi Akinlua2 min read
programming

JavaScript replaceWith() Method Explained

Learn JavaScript replaceWith() with examples for replacing an element with a node, text, or multiple nodes, plus replaceWith vs replaceChild.

Olorunfemi Akinlua2 min read
programming

JavaScript Set Remove Element with delete()

Learn how to remove an element from a Set in JavaScript using Set.delete(), check the boolean return value, clear all values, and remove object references.

Olorunfemi Akinlua3 min read
programming

JavaScript setTimeout(): Delay Code Execution

Learn JavaScript setTimeout() with delay examples, clearTimeout(), callback arguments, async behavior, and common mistakes in browsers and Node.js.

Deepak Prasad4 min read
programming

Golang reflect and golang reflection: Type, Value, Kind, Set, MakeFunc, StructOf

Golang reflection with reflect.TypeOf and reflect.ValueOf, Kind vs Type, struct fields and tags, settable values and Set, reflect.New, MakeSlice MakeMap MakeChan, MakeFunc wrappers, StructOf limits, Value.Call, …

Tuan Nguyen7 min read
programming

Go “Cannot Find Package” / Not in GOROOT (Even If GOPATH Is Set)

Why Go says cannot find package or package is not in GOROOT (or GOROOT/GOPATH), how modules fix it, and fixes for go build, go install, and the -o with multiple packages error.

Tuan Nguyen5 min read
programming

JavaScript timestamp: get, generate, and convert epoch time

javascript timestamp, js timestamp, javascript get timestamp, timestamp javascript, javascript generate timestamp: Date.now, getTime, Unix seconds, ISO strings, performance.now, with Node-verified output.

Olorunfemi Akinlua4 min read