Expose type level api

[Kingwl]

Search Terms

plugin, type, intrinsic, api

Suggestion

Now we have intrinsic type for template literal type.

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Could we release the type level api for customize the behavior of type?

Use Cases

For example

type ToNumber<T extends string> = intrinsic

type Plus<T extends number, U extends number> = intrinsic

Related:

• Math with Number Literal Type #26382
• Allow "Compiler Plugins" #16607

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, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.