Handling Array Destructuring with Default Values in TypeScript: Unexpected Behavior with Optional Properties
I need some guidance on I'm collaborating on a project where After trying multiple solutions online, I still can't figure this out. I am encountering an unexpected behavior when trying to use array destructuring with default values in TypeScript, especially when dealing with optional properties in an interface. In my case, I have a function that returns an array of values, some of which may be undefined. I'm trying to provide default values during destructuring, but the defaults are not applied as expected. Here's a simplified version of my setup: ```typescript interface UserConfig { username?: string; age?: number; } function getUserConfig(): [string, number] { // Simulating a user config that may have some undefined properties return [undefined, 25]; // username is undefined } const [username = "Guest", age = 18] = getUserConfig(); console.log(`Username: ${username}, Age: ${age}`); // Expected: "Guest, Age: 25" ``` However, this logs `Username: undefined, Age: 25`. It seems that the default value for `username` is not being applied correctly. I tried adding type annotations and ensuring that TypeScript recognizes the destructured array, but the issue persists. I also attempted to explicitly check for `undefined` before destructuring: ```typescript const config = getUserConfig(); const username = config[0] !== undefined ? config[0] : "Guest"; const age = config[1] !== undefined ? config[1] : 18; console.log(`Username: ${username}, Age: ${age}`); ``` This works, but it feels like there should be a cleaner way to achieve this with destructuring. Is there any specific part of TypeScript's handling of default values during array destructuring that I might be missing? I'm using TypeScript version 4.5.2. Any insights or best practices would be greatly appreciated! What am I doing wrong? I'm working in a Windows 10 environment. I'd be grateful for any help. I'm open to any suggestions. My team is using Typescript for this microservice. Any pointers in the right direction?