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Matt Godbolt sold me on Rust by showing me C++

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611 points LorenDB | 1 comments | 06 May 25 17:51 UTC | HN request time: 0.001s | source
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grumbel ◴[06 May 25 18:33 UTC] No.43908210[source]▶
There is '-Wconversion' to catch things like this. It will however not trigger in this specific case since g++ assumes converting 1000.0 to 1000 is ok due to no loss in precision.

Quantity(100) is counterproductive here, as that doesn't narrow the type, it does the opposite, it casts whatever value is given to the type, so even Quantity(100.5) will still work, while just plain 100.5 would have given an error with '-Wconversion'.

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b5n ◴[06 May 25 19:04 UTC] No.43908555[source]▶
> -Wconversion ... assumes converting 1000.0 to 1000 is ok due to no loss in precision.

Additionally, `clang-tidy` catches this via `bugprone-narrowing-conversions` and your linter will alert if properly configured.

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kelnos ◴[06 May 25 19:25 UTC] No.43908717[source]▶
My opinion is that if you need to run extra tools/linters in order to catch basic errors, the language & its compiler are not doing enough to protect me from correctness bugs.

I do run clippy on my Rust projects, but that's a matter of style and readability, not correctness (for the most part!).

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1. throwaway76455 ◴[06 May 25 21:43 UTC] No.43909947[source]▶
Setting up clang-tidy for your IDE isn't really any more trouble than setting up a LSP. If you want the compiler/linter/whatever to reject valid code to protect you from yourself, there are tools you can use for that. Dismissing them just because they aren't part of the language (what, do you expect ISO C++ to enforce clang-tidy usage?) is silly.