There isn't straightforward instruction on receiving a string as a variable in the std::io documentation, but I figured this should work:
use std::io;
let line = io::stdin().lock().lines().unwrap();
But I'm getting this error:
src\main.rs:28:14: 28:23 error: unresolved name `io::stdin`
src\main.rs:28 let line = io::stdin.lock().lines().unwrap();
^~~~~~~~~
Why?
I'm using a nightly Rust v1.0.
Here's the code you need to do what you are trying (no comments on if it is a good way to go about it:
use std::io::{self, BufRead};
fn main() {
let stdin = io::stdin();
let line = stdin.lock()
.lines()
.next()
.expect("there was no next line")
.expect("the line could not be read");
}
If you want more control over where the line is read to, you can use Stdin::read_line. This accepts a &mut String to append to. With this, you can ensure that the string has a large enough buffer, or append to an existing string:
use std::io::{self, BufRead};
fn main() {
let mut line = String::new();
let stdin = io::stdin();
stdin.lock().read_line(&mut line).expect("Could not read line");
println!("{}", line)
}
read_line() example, wouldn't it be more appropriate to use .ok().expect() pattern for the return value? You're not doing anything with the unwrap()ped value.
unwrap a Result, the error value will be used as the panic message. With your example, you'd need to provide an error message for expect, which might be more appropriate for your use case.
iowas renamedold_ioafter that release, and it is indeed on the way out, but not yet completely superseded by the newiomodule. First you need to figure out where you stand: Are you using 1.0.0-alpha or are you tracking nightlies?