A Gantt chart shows tasks as bars on a timeline, with dependencies between them. In React you have two sensible routes: install a library, or build a small chart yourself with CSS grid. This guide does both. The library part uses gantt-task-react, which is free, MIT-licensed, and gives you dependency arrows, drag and resize, progress … Read more >>
You cannot use React hooks inside a class component. Hooks only work in function components and in custom hooks, and React throws an error if you call one from a class. There are three practical ways round it: wrap the class in a small function component that calls the hook and passes the values down … Read more >>
A React component not rendering is almost never a React bug. In the great majority of cases it is one of a handful of ordinary mistakes: the tag starts with a lower-case letter, the function forgot its return, the import does not match the export, && put a 0 on the page instead of your … Read more >>
To use a React error boundary with functional components, you still need one class: React has no hook that catches rendering errors, so the boundary itself has to be a class component even in an app made entirely of function components. You write that class once and wrap your function components in it. The usual … Read more >>
An array of objects in TypeScript is declared by describing one object and adding []: const products: Product[] = […], where Product is an interface or a type alias. Array<Product> means the same thing. Once the array is typed, the compiler checks every property you write and every property you read, which is the whole … Read more >>
To filter an array of objects in TypeScript, pass filter() a function that tests a property: orders.filter(order => order.status === “shipped”). You get a new array of the same object type, the original is untouched, and the compiler checks every property name as you type it. This guide covers filtering by one property and by … Read more >>
To sort an array in TypeScript, call sort() with a compare function: numbers.sort((a, b) => a – b) for numbers and names.sort((a, b) => a.localeCompare(b)) for text. Swap a and b for descending order. Without a compare function sort() turns every element into a string first, which is why [100, 25, 9, 1000, 3] comes … Read more >>
To filter an array in TypeScript, call filter() with a function that returns true for the elements you want to keep: temperatures.filter(temp => temp > 80). It returns a new array and never changes the original, so the result of filtering a number[] is a number[]. The one place TypeScript surprises people is removing undefined … Read more >>
When I build small Python automation scripts, I often need to inspect values at the binary level. This happens when I work with permission flags, device status codes, color values, or compact settings stored as a single number. A decimal value like 13 is easy to read, but 0b1101 shows exactly which individual bits are switched on. Python makes … Read more >>
A customer-name cleanup script looks fine until someone enters “José”, “Megan O’Connor”, or an emoji in a notes field. When you print the value, terminals, log files, and API payloads do not always show those characters the same way. I have used Python’s ascii() function most often while debugging text pulled from CSV files, APIs, and form … Read more >>
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