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TypeScript class with generic constraints optimization guide as expected in method overloads

👀 Views: 91 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-14
typescript generics class overloading TypeScript

I've been working on this all day and I can't seem to get I'm sure I'm missing something obvious here, but I'm working on a personal project and I'm having trouble with a TypeScript class where I want to use generics with method overloads..... I have a class `Storage<T>` that is designed to store items of any type, but I'm working with issues when trying to create overloaded methods for adding and retrieving items. The method signatures seem to conflict, and TypeScript is throwing an behavior saying, ``` Argument of type 'string' is not assignable to parameter of type 'T'. ``` Here's a simplified version of what I've implemented: ```typescript class Storage<T> { private items: T[] = []; add(item: T): void; add(item: T[]): void; add(item: T | T[]): void { if (Array.isArray(item)) { this.items.push(...item); } else { this.items.push(item); } } get(index: number): T { return this.items[index]; } } const stringStorage = new Storage<string>(); stringStorage.add('Hello'); stringStorage.add(['World', 'TypeScript']); console.log(stringStorage.get(0)); // Expected: 'Hello' console.log(stringStorage.get(1)); // Expected: 'World' ``` When I try to run this code, it compiles without issues, but when I call `stringStorage.add('Hello')`, I get the aforementioned behavior message. I've tried modifying the method definitions to separate the overloads more clearly, but the behavior continues. I also checked my TypeScript version, which is 4.5.4. Are there any specific practices I might be missing when dealing with generics and overloads in TypeScript? Any help would be greatly appreciated! Any ideas what could be causing this? I'm working on a application that needs to handle this. I'd really appreciate any guidance on this. What's the best practice here? I'm working in a Windows 10 environment. Any ideas what could be causing this?