use std::fs::File; use std::io::prelude::*; use std::path::Path; pub fn read_json_file(filename: &str) -> String { let path = Path::new(filename); let display = path.display(); let mut file = match File::open(&path) { Err(why) => panic!("couldn't open {}: {}", display, &why), Ok(file) => file, }; let mut s = String::new(); if let Err(why) = file.read_to_string(&mut s) { panic!("couldn't read {}: {}", display, &why); }; s }