Rust E0191

error

~/D/R/firmata git:master ❯❯❯ cargo build                                                                                      
   Compiling firmata v0.1.0 (file:///Users/zach/Development/Rust/firmata)
src/lib.rs:9:15: 9:25 error: the value of the associated type `Settings` (from the trait `serial::SerialPort`) must be specified [E0191]
src/lib.rs:9     port: &'a SerialPort,
                           ^~~~~~~~~~
error: aborting due to previous error
Could not compile `firmata`.

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lib.rs

extern crate serial;

use std::path::Path;
use serial::prelude::*;


struct FirmataBoard<'a> {
    port: &'a SerialPort,
    port_path: Path,
}

impl<'a> FirmataBoard<'a> {
    pub fn connect(path: &Path) -> serial::Result<FirmataBoard<'a>> {
        let mut port = try!(serial::open(&path.as_os_str()));

        Ok(FirmataBoard {
            port:      port,
            port_path: path,
        })
    }
}