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use std::fs::File;
use std::io::BufReader;
use std::io::prelude::*;
fn main() -> std::io::Result<()> {
let file = File::open("foo.txt")?;
let mut buf_reader = BufReader::new(file);
let mut contents = String::new();
buf_reader.read_to_string(&mut contents)?;
assert_eq!(contents, "Hello, world!");
Ok(())
}
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use std::fs::File;
use std::io::{self, prelude::*, BufReader};
fn main() -> io::Result<()> {
let file = File::open("foo.txt")?;
let reader = BufReader::new(file);
for line in reader.lines() {
println!("{}", line?);
}
Ok(())
}
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use std::fs;
fn main() {
let content = match fs::read_to_string("Cargo.toml") {
Result::Ok(value) => value,
Result::Err(error) => panic!("{}", error)
};
println!("{}", content)
}