Course tips and study guides
Study plans, exam and interview preparation, projects and placements, from people a year or two ahead and the UniCircle team. Every tip names its author and is checked by an editor before it appears.
Topics#javascript#html#java#sql#react#accessibility#dsa#interview#nodejs#arrays#error handling#forms#oop#placements#postgresql#abstract classes#acid#aggregates
7 tips tagged #javascript
- TipEngineeringUndergraduateThe this keyword in JavaScript, explained with four rulesHow this is decided at call time, why arrow functions behave differently, and how to fix the lost-this bug in callbacks.#javascript#this#arrow functions#bindUniCircle team1 min
- GuideEngineeringUndergraduateDOM events: bubbling, delegation and preventDefaultHow a click travels through the page, why one listener on a parent can handle a hundred buttons, and when to stop default browser behaviour.#javascript#dom#events#event delegationUniCircle team1 min
- GuideEngineeringUndergraduatePromises and async/await without the confusionWhat a promise is, how async and await make asynchronous code read top to bottom, how to handle errors, and how to run independent tasks in parallel.#javascript#promises#async await#error handlingUniCircle team2 min
- GuideEngineeringUndergraduateJavaScript array methods you will use every daymap, filter, reduce, find, some, every and sort explained with one small data set, plus the sort mistake that catches almost everyone.#javascript#arrays#map filter reduce#sortUniCircle team2 min
- TipEngineeringUndergraduate== versus === and truthy values in JavaScriptWhy loose equality surprises people, the short list of falsy values, and safe ways to check for missing values with ?? and ?.#javascript#equality#truthy#nullishUniCircle team1 min
- GuideEngineeringUndergraduateJavaScript closures in 10 minutesWhat a closure is, why a function remembers the variables around it, and three places closures show up in real code and in interviews.#javascript#closures#functions#interviewUniCircle team2 min
- GuideEngineeringUndergraduatevar, let and const in JavaScript, and what hoisting really meansThe three ways to declare a variable, how their scope differs, what the temporal dead zone is, and a simple rule for which one to use.#javascript#let#const#hoistingUniCircle team2 min
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