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.
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.
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.
JavaScript Recursive Generator with yield* Examples
Learn JavaScript recursive generators with function*, yield, yield*, tree traversal, converting generators to arrays, and practical examples.
JavaScript Pattern Matching with RegExp Examples
Learn JavaScript pattern matching with regular expressions using search(), match(), matchAll(), replace(), split(), and the RegExp constructor.
JavaScript Optional Parameters and Default Values
JavaScript optional parameters: default parameters, undefined vs null, options objects, destructuring defaults, and arguments.length patterns.
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.
JavaScript Promise.resolve(): Create Resolved Promises
Learn Promise.resolve() in JavaScript with resolved values, existing promises, thenables, async functions, and Promise.reject comparison.
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).
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.
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.
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.
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().
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.
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.
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.
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.
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.
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.
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.
JavaScript replaceWith() Method Explained
Learn JavaScript replaceWith() with examples for replacing an element with a node, text, or multiple nodes, plus replaceWith vs replaceChild.
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.
JavaScript setTimeout(): Delay Code Execution
Learn JavaScript setTimeout() with delay examples, clearTimeout(), callback arguments, async behavior, and common mistakes in browsers and Node.js.
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, …
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.
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.
JavaScript loop through object: forEach, keys, entries (javascript foreach object)
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JavaScript get current date and time: new Date, UTC fields, and strings
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JavaScript Keyboard Events: keydown, keyup, and keypress
JavaScript keyboard events: keydown, keyup, deprecated keypress, KeyboardEvent.key and code, repeat, preventDefault. happy-dom–style notes describe simulated output; DOM excerpts use `{run=false}` where appropriate.
Global variable in JavaScript: globalThis, var, strict mode, and multiple files
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