Re: [RFC PATCH 1/1] Add a type for errors

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi brian

On 02/10/2024 23:04, brian m. carlson wrote:
On 2024-10-02 at 09:54:52, Phillip Wood wrote:
On 30/09/2024 23:03, brian m. carlson wrote:
Part of the reason it works well in rust is that it supports discriminated
unions with pattern matching and has the "?" macro for early returns. In C
the code ends up being quite verbose compared to taking a pointer to error
struct as a function parameter and returning a boolean success/fail flag.

     struct git_error e;
     struct object_id oid;

     e = repo_get_oid(r, "HEAD", &oid);
     if (!GIT_ERROR_SUCCESS(e))
         return e;

With a boolean return we can have

     struct object_id oid;

     if (repo_get_oid(r, "HEAD", &oid, e))
         return -1;

where "e" is a "struct git_error*" passed into the function.

Yes, I agree that this is more verbose than in Rust.  If we were using
Rust (which is a thing I'm working on), then we'd have nicer error
handling, but for now we don't.

However, Go still uses this kind of error handling, and many people use
it every day with this limitation, so I don't think it's too awful for
what we're getting.

I feel like I'm missing something - what is the advantage of returning an error struct rather than passing it as a parameter that makes the inconvenience of handling the return value worth while?

In conclusion I like the general idea but have concerns about the verbosity
of returning an error struct. It would be helpful to see some examples of
this being used to see how it works in practice.

If I send a v2, I'll try to wire up some code so folks can see some
examples.

I think that would be really helpful. A couple of examples in the cover letter showing how you'd convert some function from our codebase would give us an idea of what using this api would look like in practice.

Best Wishes

Phillip





[Index of Archives]     [Linux Kernel Development]     [Gcc Help]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [V4L]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]     [Fedora Users]

  Powered by Linux