DashCase and CamelCase intrinsic string types, or similar

Search Terms

dashcase snakecase

Suggestion

It would be great to also have DashCase and CamelCase and similar!

Use Cases

It is common in DOM libs to map from JS camelCase properties to DOM dash-case attributes (f.e. el.fooBar = 123 and <el foo-bar="123">), or CapitalizedClass names to dash-case custom element names (f.e. class FooBar extends HTMLElement and <foo-bar>).

Examples

type T1 = Dashcase<'fooBar' | 'BarBaz'> // 'foo-bar' | 'bar-baz'
type T2 = Camelcase<'foo-bar' | 'bar-baz'> // 'fooBar' | 'barBaz'

Or similar.

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.

Start with the requested DashCase and CamelCase examples and review how TypeScript currently defines intrinsic string types. Clarify casing semantics and the scope of “or similar” before proposing an implementation. Done means the accepted type-level transformations are supported and tests cover the examples in the issue.