baoyachi

I would like to. Could you please provide detail example about?

That's a good suggestion. I'll think about it. @jaskij THX.

solution ref : https://github.com/aptos-labs/aptos-core/blob/c7978de51c52a5f6517c88f3ae24d9c241d4beb7/crates/aptos-telemetry/src/build_information.rs

ref:https://github.com/strawlab/iana-time-zone/pull/55/files#diff-73e17259d77e5fbef83b2bdbbe4dc40a912f807472287f7f45b77e0cbf78792dL79-R90

I'm try to do it.

ref: https://crates.io/crates/document-features

Also see : https://crates.io/crates/duration-str

Why not replace `some_more_fn ` with `and_then`. Ref :[and_then](https://doc.rust-lang.org/stable/std/?search=and_then)

1. Generated struct object 2. Codegen use by [TokenStream](https://doc.rust-lang.org/stable/proc_macro/struct.TokenStream.html)

@YdrMaster I will solve this problem soon.