--- title: "Luca Zanzottera (@Zanz) | Hashnode" description: "Luca Zanzottera (@Zanz) writes on Hashnode. Read their latest articles and follow their work." url: "https://hashnode.com/@Zanz" --- @Zanz # Luca Zanzottera @Zanz · Italy · Joined August 2020 ### [GIT: remove local untracked files](https://papidev.hashnode.dev/git-remove-local-untracked-files?utm_source=hashnode&utm_medium=feed) Sometimes you just want to get rid of all the local untracked files. If you are sure of what you're doing (because there is no way to get back ! ) you can use git clean To check before , in a safe way, which files you're going to delete ---> -n ... 2 min read · [papidev.hashnode.dev](https://papidev.hashnode.dev/git-remove-local-untracked-files?utm_source=hashnode&utm_medium=feed) [Feb 21, 2021](https://hashnode.com/posts/git-remove-local-untracked-files/6031aedaf51caf444856270c) ### [REACT : "custom validator" for String Props](https://papidev.hashnode.dev/react-custom-validator-for-string-props?utm_source=hashnode&utm_medium=feed) Prop-types is a library that allows to introduce some validation on the props we pass to React components. It works only in development mode , writing warning/errors in the console when a prop passed to a component is not valid, allowing us to disc... 3 min read · [papidev.hashnode.dev](https://papidev.hashnode.dev/react-custom-validator-for-string-props?utm_source=hashnode&utm_medium=feed) [Nov 19, 2020](https://hashnode.com/posts/react-custom-validator-for-string-props/5fb5bb9b08ea5d7167d6f31b) ### [REACT: children.map is not a function](https://papidev.hashnode.dev/react-childrenmap-is-not-a-function?utm_source=hashnode&utm_medium=feed) I come across this error today in my Next.js app. When I found the solution I realized that I had already stumbled upon it not so long ago ... but I had forgotten. That's the reason why I'm writing this little post :-) This piece of code ... exp... 2 min read · [papidev.hashnode.dev](https://papidev.hashnode.dev/react-childrenmap-is-not-a-function?utm_source=hashnode&utm_medium=feed) [Nov 17, 2020](https://hashnode.com/posts/react-childrenmap-is-not-a-function/5fb3a7ff595a24599b2f388f) ### [NEXT.js: Selector is not pure](https://papidev.hashnode.dev/nextjs-selector-is-not-pure?utm_source=hashnode&utm_medium=feed) Today I stumbled upon this error in my Next.js application using CSS Modules Syntax error: Selector "img" is not pure (pure selectors must contain at least one local class or id) The reason was that , in one of my CSS modules ( that is a file like... 2 min read · [papidev.hashnode.dev](https://papidev.hashnode.dev/nextjs-selector-is-not-pure?utm_source=hashnode&utm_medium=feed) [Nov 10, 2020](https://hashnode.com/posts/nextjs-selector-is-not-pure/5faa72d46bd0b3538653d318) ### [JAVASCRIPT: Check if an Object exists and is not empty](https://papidev.hashnode.dev/javascript-check-if-an-object-exists-and-is-not-empty?utm_source=hashnode&utm_medium=feed) To check if an object "myObj" exists ( it's neither null nor undefined) and it's not empty we can use this expression : myObj && Object.keys(myObj).length !== 0 && myObj.constructor === Object Explanation myObj if it evaluates to true, "myObj... 2 min read · [papidev.hashnode.dev](https://papidev.hashnode.dev/javascript-check-if-an-object-exists-and-is-not-empty?utm_source=hashnode&utm_medium=feed) [Oct 9, 2020](https://hashnode.com/posts/javascript-check-if-an-object-exists-and-is-not-empty/5f80e4b05841661b519d0010)