[OT] Error handling in C3 language

May 29

Kagamin

May 29

Ali Çehreli

Oct 24

Vinod K Chandran

Oct 25

Kapendev

// Function returning an Optional fn int? maybe_func() { /* ... */ } fn void? test() { // ❌ This will be a compile error // maybe_function() returns an Optional // and 'bar' is not declared Optional: // int bar = maybe_function(); int bar = maybe_function()!; // ✅ The above is equivalent to: // int? temp = maybe_function(); // if (catch excuse = temp) return excuse?; // Now temp is unwrapped to a non-Optional int bar = temp; // ✅ This is OK }

On 5/29/25 1:18 PM, Kagamin wrote: > But striving to be evolution of C, faults look like error code > singletons and apparently don't carry much information. Same here. I've been using a macro system in a C++ library that exposes a C API. All implementation functions return an optional type that automatically errors if not checked. Equivalents of enforce(), assert(), etc. automatically return an invalid optional. Here is your point: There is a constant-length buffer that collects a backlog of error messages from function calls. Exhausting the buffer is not an error; the lowest-level error messages are retained. That buffer is just 4K, which is 0 bytes to my eyes :). The caller of the C API receives a C array of error strings that they can print to see exactly what happened. Sweet... Oh... oh... and all formatted error messages are actually generated in a development build even when there are no errors, to prove that error messages will render and look correct when generated. (The buffer is a lot larger in that case, not 4K.) Very sweet indeed... :) Ali

October 25

Re: [OT] Error handling in C3 language

Posted by Kapendev
in reply to Vinod K Chandran

Permalink

Kapendev

Posted in reply to Vinod K Chandran

Permalink

On Friday, 24 October 2025 at 11:07:40 UTC, Vinod K Chandran wrote:

On Thursday, 29 May 2025 at 20:18:27 UTC, Kagamin wrote:

https://c3-lang.org/language-common/optionals-advanced/
The language is quite nice, resembles BetterC, but also the first ergonomic language where I see the Result type in action. Result is also used for nullable types.

I am also a fan of C3, done a medium size hobby project in C3 (9K LOC). Though, I don't like the error handling feature in C3 very much. I mean it's not bad, but it's not simple. I like Odin's simplicity.

Old forum post :)
Anyway, Odin just has multiple return values.
The C3 way is OK for basic things and I use something similar in my D code. It's a Maybe/Option type, but with an error code instead of a bool. I don't think you should make that part of your language, or do it the way C3 did, but ehh.

Forums