Function type definition with anonymous arguments and optional parentheses for single argument

Suggestion

🔍 Search Terms

anonymous type argument, optional parentheses

List of keywords you searched for before creating this issue. Write them down here so that others can find this suggestion more easily and help provide feedback.

✅ Viability Checklist

My suggestion meets these guidelines:

• 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 feature would agree with the rest of TypeScript's Design Goals.

⭐ Suggestion

Like a anonymous function and anonymous type, it could be nice a type definition with anonymous arguments. Also, as in function definition, function type definition with single argument, the parentheses could be optional.

📃 Motivating Example

This simple enhancement let a more clean and lean code syntaxe.

💻 Use Cases

// currently
function f(callback:(...args: string[]) => void) { ... }

// anonymous arguments
function f(callback: (...string[]) => void) { ... }

// anonymous argument + optional parentheses
function f(callback: ...string[] => void) { ... }

The issue identifies no implementation files, entry points, or tests; start with its motivating examples and requested syntax forms. Done would mean the anonymous-argument and optional-parentheses forms are accepted as described without changing emitted JavaScript, with regression coverage added.