Function syn::parse_file

source ·
pub fn parse_file(content: &str) -> Result<File>
Expand description

Parse the content of a file of Rust code.

This is different from syn::parse_str::<File>(content) in two ways:

  • It discards a leading byte order mark \u{FEFF} if the file has one.
  • It preserves the shebang line of the file, such as #!/usr/bin/env rustx.

If present, either of these would be an error using from_str.

§Examples

use std::error::Error;
use std::fs::File;
use std::io::Read;

fn run() -> Result<(), Box<dyn Error>> {
    let mut file = File::open("path/to/code.rs")?;
    let mut content = String::new();
    file.read_to_string(&mut content)?;

    let ast = syn::parse_file(&content)?;
    if let Some(shebang) = ast.shebang {
        println!("{}", shebang);
    }
    println!("{} items", ast.items.len());

    Ok(())
}