How to use Rc<BufReader<File>> ? I get error at line 8.

Rc won't help you with this at all. yes, lines takes BufReader by Self, however, the Read trait is implemented for &mut T where T: Read, so you only need to make Self == &mut BufReader. the way you do this is by (&mut buf_reader).lines()

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01.12.2021

Brian Автор вопроса

Artem Starikov
Rc won't help you with this at all. yes, lines ta...

😂, What vodoo is this? can you explain more.

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01.12.2021

Artem Starikov

Brian
😂, What vodoo is this? can you explain more.

just do let reader = BufReader::new(file); and use (&mut reader).lines()

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01.12.2021

Raymond

Brian
😂, What vodoo is this? can you explain more.

Yup. You overthinked on that.

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01.12.2021

Brian Автор вопроса

Artem Starikov
just do let reader = BufReader::new(file); and use...

Hmm... can't borrow mutably, are you sure we don't need RefCell to make that possible? otherwise make reader mut?

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01.12.2021

Artem Starikov

Brian

Hmm... can't borrow mutably, are you sure we don't...

let mut reader`is enough. you don't need `RefCell here at all

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01.12.2021

Raymond

Brian

Hmm... can't borrow mutably, are you sure we don't...

You overengineered it. You don't need it there.

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01.12.2021

Brian Автор вопроса

Artem Starikov
let mut reader`is enough. you don't need `RefCell ...

Now notice the output. it doesn't read the lines in the file anymore. 😂 The line: println!("LINE:{}",line.unwrap()); Now never runs.

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01.12.2021

Brian Автор вопроса

Artem Starikov
let mut reader`is enough. you don't need `RefCell ...

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01.12.2021

Artem Starikov

Brian

Now notice the output. it doesn't read the lines i...

well yes, the first call to lines() read the whole file, so the second call to lines() cannot read any lines past the file end

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01.12.2021

Brian Автор вопроса

Artem Starikov
well yes, the first call to lines() read the whole...

😂😂, so would have rather read those values and stored in a Vec<String> 😂... No need for mut, thanks.

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01.12.2021

Artem Starikov

Brian
😂😂, so would have rather read those values and sto...

actually, something along these lines would work: let lines = file.lines() .inspect(|line| println!("LINE: {}", line.unwrap()) .count();

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01.12.2021

Brian Автор вопроса

Artem Starikov
actually, something along these lines would work: ...

Thanks.

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01.12.2021

Raymond · Accepted Answer

Raymond

Brian

You're using Rc. Consider cloning.

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01.12.2021

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How to use Rc<BufReader<File>> ? I get error at line 8.

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