Pfthb

Currently, I'm turning a Result into an instance of my error enum that impls Fail like this:

fn bbswitch_write(data: &str) -> Result<(), BbswitchError> 
 match fs::write("/proc/acpi/bbswitch", data) 
 Ok(_) => Ok(()),
 Err(e) => Err(BbswitchError::BbswitchNotAvailable cause: e .into()),
 

but this feels very verbose, and I'd rather not write a four-line match statement every time I do something like this:

let contents = fs::read_to_string("/proc/acpi/bbswitch").expect("bbswitch not available");

Is there something I'm doing wrong that's making error handling unreasonably difficult, or a way I could structure something better to make it more convenient?

The rest of my code looks something like this:

#[macro_use]
extern crate failure;

use std::fs;
use std::process::exit;
use failure::Error;

#[derive(Debug, Fail)]
enum BbswitchError 
 #[fail(display = "bbswitch not available")]
 BbswitchNotAvailable 
 #[fail(cause)]
 cause: std::io::Error,
 ,


fn bbswitch_write(data: &str) -> Result<(), Error> 
 match fs::write("/proc/acpi/bbswitch", data) 
 Ok(_) => Ok(()),
 Err(e) => Err(BbswitchError::BbswitchNotAvailable cause: e .into()),
 


fn power_on() -> Result<(), Error> 
 bbswitch_write("ON")?;
 Ok(())


fn main() 
 match power_on() 
 Ok(_) => ,
 Err(_) => exit(1),
 

That very simple just use map_err():

fs::write("/proc/acpi/bbswitch", data)
 .map_err(|e| BbswitchError::BbswitchNotAvailable cause: e .into())