Fails: Get len of a file, using rustc 1.0.0-dev (built 2015-02-22)

len.rs

use std::io::prelude::*;
use std::fs::File;
use std::fs::Metadata;

fn main() {
    fn len() -> std::io::Result<()> {
        let mut f = try!(File::open("len.rs"));
        println!("{}", f.metadata().len());
        Ok(())
    }
}

output

$ rustc len.rs 
len.rs:8:37: 8:42 error: type `core::result::Result<std::fs::Metadata, std::io::error::Error>` does not implement any method in scope named `len`
len.rs:8         println!("{}", f.metadata().len());
                                             ^~~~~
error: aborting due to previous error

Please comment here if you can fix this issue.

According to klutzy, the answer was try!(f.metadata()).len()