Evaluate using annotations with typeguard-style instrumentation

[dkamm]

Hey @patrick-kidger!

I got this idea through our discussion in agronholm/typeguard#353. Wanted to create an issue here since it's unrelated to typeguard.

What if jaxtyping had its own typeguard-style instrumentation?

We could write annotations like Float[T, S] = Annotated[T, Shape(S), DType("Float")], and the instrumentation could consume them to validate.

Pros

• More control over validation, solves Error message could include more shape information #6
• Seems more in the spirit of PEP 593
• Gets rid of the Annotated as Float hack

Cons

• It's instrumentation
• Could be overkill

[patrick-kidger]

That is to say, you're proposing to write an entirely new runtime type checker? That is what would be required, in order to handle cases like tuple[Float[Array, "foo"], ...], in which the jaxtyping annotations are nested inside arbitrarily many other annotations. That seems like a lot of work when we already have both typeguard and beartype which are mostly-good-enough already.

I believe the Float as Annotated hack will always be required for static type checking compatibility.

[dkamm]

Good point- closing