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The Hidden Rules Behind Rust Functions & Closures (blog.cuongle.dev)
submitted 6 months ago by turbohz@programming.dev to c/rust@programming.dev
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[-] kubica@fedia.io 3 points 6 months ago

It's quite annoying at the beginning that the errors you get make you believe that 'closure' is a type in itself, because the errors themselves quote the word as if it was some kind of type, but then you can't specify something like let f: closure = ....

[-] calcopiritus@lemmy.world 9 points 6 months ago* (last edited 6 months ago)

Well, the closure has a type. Just you cannot declare it. That's why you do "impl Fn" instead. Because you know that whatever type the close is, it implements the "Fn" trait.

[-] BatmanAoD@programming.dev 3 points 6 months ago

Do you have a different recommendation for how to display unnameable types in error messages? I'm sure the compiler team would consider any suggestions.

[-] tjunge@twit.social 2 points 6 months ago

@turbohz Very nice summary, thanks!

this post was submitted on 11 Sep 2025
39 points (97.6% liked)

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