Description
🔍 Search Terms
Currently, in TypeScript, when we define a constructor (concise way), parameters do not automatically become class properties unless explicitly marked with public, private, or protected.
✅ Viability Checklist
- This wouldn't be a breaking change in existing TypeScript/JavaScript code
- This wouldn't change the runtime behavior of existing JavaScript code
- This could be implemented without emitting different JS based on the types of the expressions
- This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
- This isn't a request to add a new utility type: https://github.com/microsoft/TypeScript/wiki/No-New-Utility-Types
- This feature would agree with the rest of our Design Goals: https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals
⭐ Suggestion
I propose that constructor parameters should default to public if no access modifier is specified.
This means:
-> Explicit access modifiers (private, protected) should still behave as expected.
->If no modifier is given, TypeScript should automatically treat the parameter as public.
📃 Motivating Example
Current Behaviour:
class Student {
constructor(public name: string, public age?: number, public address?: string) {}
}
Suggested Behaviour:
class Student {
constructor(name: string, age?: number, address?: string) {}
}
💻 Use Cases
Why This Change?
✅ Reduces Redundancy – No need to explicitly write public when it's the default behavior.
✅ Improves Developer Experience – Constructor parameters are typically meant to be class properties, so it makes sense for TypeScript to assume public.
✅ Keeps Code Clean & Readable – Avoids unnecessary boilerplate.