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Merge pull request #1912 from wowinter13/improve-drop-docs
Add more examples @ drop.md
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src/trait/drop.md

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@@ -54,4 +54,56 @@ fn main() {
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}
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```
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For a more practical example, here's how the `Drop` trait can be used to automatically
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clean up temporary files when they're no longer needed:
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```rust,editable
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use std::fs::File;
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use std::path::PathBuf;
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struct TempFile {
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file: File,
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path: PathBuf,
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}
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impl TempFile {
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fn new(path: PathBuf) -> std::io::Result<Self> {
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// Note: File::create() will overwrite existing files
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let file = File::create(&path)?;
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Ok(Self { file, path })
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}
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}
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// When TempFile is dropped:
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// 1. First, the File will be automatically closed (Drop for File)
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// 2. Then our drop implementation will remove the file
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impl Drop for TempFile {
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fn drop(&mut self) {
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// Note: File is already closed at this point
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if let Err(e) = std::fs::remove_file(&self.path) {
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eprintln!("Failed to remove temporary file: {}", e);
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}
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println!("> Dropped temporary file: {:?}", self.path);
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}
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}
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fn main() -> std::io::Result<()> {
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// Create a new scope to demonstrate drop behavior
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{
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let temp = TempFile::new("test.txt".into())?;
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println!("Temporary file created");
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// File will be automatically cleaned up when temp goes out of scope
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}
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println!("End of scope - file should be cleaned up");
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// We can also manually drop if needed
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let temp2 = TempFile::new("another_test.txt".into())?;
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drop(temp2); // Explicitly drop the file
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println!("Manually dropped file");
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Ok(())
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}
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```
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[Drop]: https://doc.rust-lang.org/std/ops/trait.Drop.html

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