Is it worth it to re-export some libraries in ic-cdk?

Developers
1

As we can see here, ic-cdk re-exports some library functions, mainly candid and serde.

I think if those crates are necessary for using ic-cdk, it would be much clearer to let canister developers import candid or serde directly by themselves.

  1. When you want to use ic-cdk, you still have to import candid and serde in most cases.
  2. And it’s annoying the compiler throws errors when you want to use only candid (I’m not sure if this is a bug of the rust compiler):

[dependencies] of ic00_types should only need candid, and ic-cdk is not imported in reality, but there are a lot of strange errors:

   --> /Users/x/.cargo/git/checkouts/ic-55f61c774f0feae0/551408d/rs/types/ic00_types/src/lib.rs:997:10
    |
997 | #[derive(CandidType, Deserialize)]
    |          ^^^^^^^^^^ not found in `ic_cdk::export::candid::types`
    |
    = note: this error originates in the derive macro `CandidType` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider importing one of these items
    |
5   | use candid::types::TypeId;
    |
5   | use core::any::TypeId;
    |
5   | use std::any::TypeId;
    |
help: if you import `TypeId`, refer to it directly
    |
997 - #[derive(CandidType, Deserialize)]
997 + #[derive(CandidType, Deserialize)]
    | 

error[E0433]: failed to resolve: could not find `ic_cdk` in the list of imported crates

Since the open source of the ic repo in May last year, when importing the library of the ic repo as a dependency into other projects, I have often received this problem.

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2

There’s a note somewhere which says:

Note that if you are using the Rust CDK to develop Rust canisters, it is encouraged to use the Candid crate from ic_cdk::export::candid to avoid version mismatch.

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