Compared to a struct in C, Rust, Golang, or Java it takes more key presses on behalf of the programmer and only works in (/is optimized for) a narrowly specific set of circumstances.

Convenient in some ways (e.g. if you are only comfortable in JS), and does nothing useful in other contexts.

Nothing inherently wrong with it, other than it seems like a missed opportunity.

Is this more than a subset of Wordnik's Swagger?

https://swagger.io/

> Compared to a struct in C (...)

That's hardly a relevant point or meaningful comparison. The discussion is about schema validators for TypeScript/JavaScript.

Swagger uses JSON Schema to describe the data formats.

https://swagger.io/docs/specification/data-models/keywords/

This is a easier write, easier to read, compatible with JSON Schema alternative. Spartan Schema could be used instead of JSON Schema to make the document easier for humans to work with.

> At the core, is this more than a JSON-schema generator bundled with a check function? Could it be >?

> Then the meta solution will become self-evident.

> Think bigger.

Are you going to share your big idea?

Those are not in any way full alternatives to JSON schema