Suggestion: Deep Partial

[kaikaibenkai]

Suggestion

🔍 Search Terms

Sometimes I have config files like

export default defineMyConfig({
  title: 'Hello, World!',
  database: {
    port: 5330,
    password: '12348765',
  },
});

defineMyConfig will deep merge the given config options and default config.

...But what's the given options' type? Partial<T> isn't deep.

✅ 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

Adding a built-in type like DeepPartial<T>.

📃 Motivating Example

(in the fist paragraph)

💻 Use Cases

(in the fist paragraph)

[fatcerberus]

#51841 (comment)

[kaikaibenkai]

Ok then...