codeintel::block_f9dfbf3e26ea6374

fn main()

let a: usize

usize

The pointer-sized unsigned integer type.

The size of this primitive is how many bytes it takes to reference any location in memory. For example, on a 32 bit target, this is 4 bytes and on a 64 bit target, this is 8 bytes.

let v: u8

let b: usize

std::macros

macro_rules! println

Prints to the standard output, with a newline.

On all platforms, the newline is the LINE FEED character (\n/U+000A) alone (no additional CARRIAGE RETURN (\r/U+000D)).

This macro uses the same syntax as format, but writes to the standard output instead. See [std::fmt] for more information.

The println! macro will lock the standard output on each call. If you call println! within a hot loop, this behavior may be the bottleneck of the loop. To avoid this, lock stdout with io::stdout().lock():

use std::io::{stdout, Write};

let mut lock = stdout().lock();
writeln!(lock, "hello world").unwrap();

Use println! only for the primary output of your program. Use [eprintln!] instead to print error and progress messages.

See the formatting documentation in std::fmt for details of the macro argument syntax.

println!(); // prints just a newline
println!("hello there!");
println!("format {} arguments", "some");
let local_variable = "some";
println!("format {local_variable} arguments");

std::macros

macro_rules! panic