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use std::{ fs::OpenOptions, path::PathBuf };
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use anyhow::Result;

            

        

            

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use crate::RwBuilder;

            

        

            

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/// Type for building readers and writers on top of a file handle.

            

        

            

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/// It is itself an `RwBuilder`, but can't be created through one.

            

        

            

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/// This is why we call it a source.

            

        

            

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#[derive(Debug)]

            

        

            

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pub struct Builder {

            

        

            

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    /// The path of the file for which readers and writers can be created.

            

        

            

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    path: PathBuf,

            

        

            

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}

            

        

            

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impl Builder {

            

        

            

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    /// Factory function to create a builder holding on to a file path

            

        

            

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    #[must_use]

            

        

            

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    pub const fn new(path: PathBuf) -> Self {

            

        

            

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        Self { path }

            

        

            

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    }

            

        

            

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}

            

        

            

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impl RwBuilder for Builder {

            

        

            

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    type Reader = std::fs::File;

            

        

            

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    type Writer = std::fs::File;

            

        

            

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    fn reader(&self) -> Result<Self::Reader> {

            

        

            

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        let options = OpenOptions::new().read(true).open(&self.path)?;

            

        

            

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        Ok(options)

            

        

            

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    }

            

        

            

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    fn writer(&self) -> Result<Self::Writer> {

            

        

            

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        let options = OpenOptions::new().create(true).truncate(true).write(true).open(&self.path)?;

            

        

            

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        Ok(options)

            

        

            

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    }

            

        

            

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}