I was looking at the std::env::current_dir documentation and this caught my attention:
std::io::Result<()>
I thought a Result should have a T and an E. How can you substitute them with ()?
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kmdreko
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Paul Razvan Berg
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2That's a [`std::io::Result`](https://doc.rust-lang.org/std/io/type.Result.html), not a `std::result::Result`. – Brian61354270 Mar 08 '20 at 15:08
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2Does this answer your question? [Result getting unexpected type argument](https://stackoverflow.com/questions/57794849/result-getting-unexpected-type-argument) – SCappella Mar 08 '20 at 15:10
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Thanks @SCappella, both your link and Brian's answer are helpful. – Paul Razvan Berg Mar 08 '20 at 15:12
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std::io::Result is a type alias specific to the std::io module, which is defined as
type Result<T> = Result<T, ::std::io::Error>;
Essentially, it's a std::result::Result with the error type prefilled as a std::io::Error. Using this type only requires one type parameter, which corresponds to the "ok" type T in Result<T,E>.
Brian61354270
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