With Rust being comparatively new, I’ve seen far too many ways of reading and writing files. Many are extremely messy snippets someone came up with for their blog, and 99% of the examples I’ve found (even on Stack Overflow) are from unstable builds that no longer work. Now that Rust is stable, what is a simple, readable, non-panicking snippet for reading or writing files?
This is the closest I’ve gotten to something that works in terms of reading a text file, but it’s still not compiling even though I’m fairly certain I’ve included everything I should have. This is based off of a snippet I found on Google+ of all places, and the only thing I’ve changed is that the old BufferedReader
is now just BufReader
:
use std::fs::File;
use std::io::BufReader;
use std::path::Path;
fn main() {
let path = Path::new("./textfile");
let mut file = BufReader::new(File::open(&path));
for line in file.lines() {
println!("{}", line);
}
}
The compiler complains:
error: the trait bound `std::result::Result<std::fs::File, std::io::Error>: std::io::Read` is not satisfied [--explain E0277]
--> src/main.rs:7:20
|>
7 |> let mut file = BufReader::new(File::open(&path));
|> ^^^^^^^^^^^^^^
note: required by `std::io::BufReader::new`
error: no method named `lines` found for type `std::io::BufReader<std::result::Result<std::fs::File, std::io::Error>>` in the current scope
--> src/main.rs:8:22
|>
8 |> for line in file.lines() {
|> ^^^^^
To sum it up, what I’m looking for is:
- brevity
- readability
- covers all possible errors
- doesn’t panic