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by elcritch 2069 days ago
Unfortunately, it'd be impossible to work effectively with C code without `nil`. You can create objects set to `not nil`. To be fair, I've had a few points when creating a new type that I forgot to allocate a new instance properly, but option types wouldn't have saved me any work. It would've produced a similar stacktrace. I think the compiler produces a warning, but I'm still working down the warning's lists. You can see more discussion on defaulting not nil here: https://github.com/nim-lang/Nim/issues/6638
1 comments
Conlectus 2069 days ago
Having all references that are returned from C be treated as Option types would resolve this difficulty, no?

Likewise, your type system can prevent you from using uninitialized values in other languages, without the need for Option (and indeed the unwrap() call you imply you would have used) from being needed.

Though yes, I'm glad to see this is being addressed :).

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elcritch 2069 days ago
> Having all references that are returned from C be treated as Option types would resolve this difficulty, no?

Perhaps, but there's more than just returns. Dealing with most C code there's a fair bit of pointer passing and manipulation. It's nice being able to deal directly with C code and not have to worry about the impedance mismatch, but still be able to move up the type system. It's more a pragmatic choice.

> Likewise, your type system can prevent you from using uninitialized values in other languages, without the need for Option (and indeed the unwrap() call you imply you would have used) from being needed.

In this case, mostly its just me not using the type system well. :-) But that's the price I pay for a using a flexible language I can readily use in embedded work. NPE's really don't cause me any headaches compared to most of the other aspects of integrating heavily with C code in embedded systems.

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nine_k 2069 days ago
All the convenience and all the unsafety of C code while interacting with C code? Why not just use C, or C++ if expression power is needed?
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elcritch 2069 days ago
Same reason as using unsafe Rust to interface w/ C/C++, to wrap the the unsafe bits and make safer API's asap. Nim's macros also making interactions with C API's safer. To be clear, I'll be glad when Nim checks these things by default (the Z3 checker will be great for that!).
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