The AsRef Trait

Working with strings is a common requirement in real-world applications. Sometimes, you want a function that can take either a String or a &str as input without needing separate implementations. Rust's AsRef trait provides a simple way to borrow data as a reference in a generic manner, enabling functions to work with various types that can be represented as a reference to a common type.

The AsRef trait is a powerful standard library trait used for cheap conversions to a reference of another type. For example, it can be used to create a function that works with both owned (String) and borrowed (&str) string types. This approach is lightweight and avoids unnecessary allocations.

Your Task

Implement a function print_message that accepts any type that implements the AsRef<str> trait. This function should:

Accept a single argument of a generic type that implements AsRef<str>.
Borrow the input as a string slice (&str) and print it to the console using println!.

Hints

Click here to reveal hints

The AsRef trait provides a .as_ref() method to borrow a reference.
Both String and &str implement AsRef<str>, so they can be used interchangeably with this trait.

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Solutions

muemart

3 hours ago

365.68ms

100.64kb

pub fn print_message<T: AsRef<str>>(arg: T){
    println!("{0}", arg.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Christophe Mohimont

mohic

2 days ago

337.52ms

100.64kb

pub fn print_message<T>(message: T)
where
    T: AsRef<str>,
{
    println!("{}", message.as_ref())
}

amdfxlucas

5 days ago

370.76ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str>>(s: T)
{
    println!("{}", s.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

StevenCanDrink

7 days ago

350.81ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: Display>(x: T) -> () {
    println!("{}", x)
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Chih Ying Yen

xavierforge

9 days ago

542.79ms

100.64kb

pub fn print_message<T: AsRef<str>>(input: T){
    println!("{}", input.as_ref())
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Jai

jsat97

9 days ago

372.86ms

100.64kb

pub fn print_message<T> (val: T) 
    where T:AsRef<str> + std::fmt::Display {
   println!("{}",&val); 
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

undefeated_

boyboi86

11 days ago

383.89ms

100.64kb

pub fn print_message<T: AsRef<str>>(s: T) {
    println!("{}", s.as_ref())
}// Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Artem Nistuley

artemnistuley

12 days ago

359.18ms

100.64kb

pub fn print_message<T>(s: T)
where
    T: AsRef<str> + std::fmt::Display
{
    println!("{}", s);
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

GunGraveCpp

14 days ago

360.80ms

100.64kb

use core::convert::AsRef;
pub fn print_message< T: AsRef<str>>(value: T){
    println!("{}", value.as_ref());
} 
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

David Rasch

dcrasch

14 days ago

353.08ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str> + Display>(message: T) {
    println!("{}", message.as_ref());
}
    
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Lvfalue

16 days ago

393.07ms

100.64kb

pub fn print_message(s: impl AsRef<str>) {
    println!("{}", s.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Jean-baptiste JOFFRE

Indy79

19 days ago

354.28ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    // Finish the function
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

toto

20 days ago

423.94ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    // Finish the function
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

visanr

21 days ago

401.58ms

100.64kb

pub fn print_message<T: AsRef<str>>(s: T) {
    println!("{}", s.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Gurneet singh

GS-Jatt

21 days ago

421.94ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str> + Display>(str: T) {
    println!("{str}");
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

shahab-tplus

22 days ago

352.85ms

100.64kb

pub fn print_message<T: AsRef<str>>(mystr: T) {
    println!("{}", mystr.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Luka Bračun

lbracun

23 days ago

408.36ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

bzdula

23 days ago

449.83ms

100.64kb

pub fn print_message(message: impl AsRef<str>) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Ranjith Thangavel

RanjithECE24

24 days ago

345.48ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Wouter

WouterMartens

a month ago

340.84ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    println!("{}", message.as_ref());
}
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Wouter

WouterMartens

a month ago

371.62ms

100.64kb

pub fn print_message<T>(message: T)
where
    T: AsRef<str>,
{
    println!("{}", message.as_ref());
}
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Andy Randrianirina

andyslash

a month ago

385.31ms

100.64kb

pub fn print_message<T>(message: T) 
where T: AsRef<str>,
{
    println!("{}", message.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Daniel Mestas

miel-codeai

a month ago

393.71ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Christopher Kolbe

chkolbe

a month ago

359.34ms

100.64kb

pub fn print_message<T>(message: T)
where T: AsRef<str>,
{
    let reference = message.as_ref();
    println!("{}", reference);
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

aghia98

a month ago

409.57ms

100.64kb

pub fn print_message<T>(message: T)
where  T: AsRef<str>{
    println!("{}", message.as_ref());
}
// Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

baschdik

a month ago

396.10ms

100.64kb

pub fn print_message<T: AsRef<str>>(item: T){
    println!("{}", item.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

aey4

a month ago

372.14ms

100.64kb

pub fn print_message<T: AsRef<str>>(message:T){
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Evgenii Uglanov

winchest3r

a month ago

376.62ms

100.64kb

pub fn print_message<T>(msg: T)
where T: AsRef<str>
{
    println!("{}", msg.as_ref());
} 
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

thriller08

a month ago

348.80ms

100.64kb

use std::convert::AsRef;
pub fn print_message<T: AsRef<str>>(msg: T) {
    println!("{}", msg.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

manu3618

a month ago

346.22ms

100.64kb

pub fn print_message<T: AsRef<str>>(s: T) {
    println!("{}", s.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Fatih

0fatih

a month ago

353.61ms

100.64kb

pub fn print_message<T: AsRef<str>>(b: T) {
    println!("{}", b.as_ref())
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Fatih

0fatih

a month ago

387.93ms

100.64kb

pub fn print_message<T: AsRef<str>>(b: T) {
    println!("{}", b.as_ref())
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

slaws

a month ago

369.61ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: Display + AsRef<str>>(input: T) { // Finish the function
    println!("{}",input);
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Evrins Hu

evrins

a month ago

425.19ms

100.64kb

pub fn print_message<T>(msg: T)
where T: AsRef<str>
{
    println!("{}", msg.as_ref());
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

johndoe30bc

a month ago

382.65ms

100.64kb

pub fn print_message<T: AsRef<str>>(v: T) {
    println!("{}", v.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Baron Curtin

baroncurtin2

a month ago

347.93ms

100.64kb

pub fn print_message<T: AsRef<str>>(val: T) {
    println!("{}", val.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

m1031

monorail103

a month ago

363.22ms

100.64kb

pub fn print_message<T: AsRef<str>>(arg: T) {
    println!("{}", arg.as_ref())
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Evgenii Grigorenko

grevgeny

a month ago

385.46ms

100.64kb

pub fn print_message<T: AsRef<str>>(arg: T) {
    println!("{}", arg.as_ref())
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Blaze

Divakar-2508

2 months ago

342.80ms

100.64kb

pub fn print_message<S: AsRef<str>>(msg: S) {
    println!("{}", msg.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Procybit

2 months ago

358.12ms

100.64kb

pub fn print_message<T: AsRef<str>>(m: T) {
    println!("{}", m.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

FredoPo

2 months ago

346.15ms

100.64kb

pub fn print_message<T: AsRef<str>>(message: T) {
    let texte = message.as_ref();
    println!("{texte}");
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

brucecox01

2 months ago

397.82ms

100.64kb

pub fn print_message<T>(message: T) // Finish the function
where
    T: AsRef<str>,
{
    let message = message.as_ref();
    println!("{message}");
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

fwilliams42

2 months ago

389.43ms

100.64kb

pub fn print_message(message: impl AsRef<str>) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Karol Płatkowski

spoohie

2 months ago

353.52ms

100.64kb

pub fn print_message<T: AsRef<str>>(s: T) {
    println!("{}", s.as_ref())
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

xxxxsk

2 months ago

367.65ms

100.64kb

pub fn print_message<T: AsRef<str>>(t: T) { // Finish the function
    println!("{}", t.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Franklin Chen

FranklinChen

2 months ago

364.72ms

100.64kb

pub fn print_message(message: impl AsRef<str>) {
    println!("{}", message.as_ref());
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Krzysztof Atłasik

katlasik

2 months ago

346.46ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str> + Display>(str: T) {
    println!("{}", str)
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

bernardoLY19

2 months ago

385.04ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str> + Display>(t: T) {
    println!("{}", t);
}
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Miguel Ángel Allende

maallende

2 months ago

377.60ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: Display + AsRef<str>>(value: T){
    println!("{}",value)
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}

Rocky.C

cloki0610

2 months ago

366.52ms

100.64kb

use std::fmt::Display;
pub fn print_message<T: AsRef<str> + Display>(value: T) {
    println!("{}", value)
} // Finish the function
// Example usage
pub fn main() {
    // Example 1: Using a &str
    print_message("Hello, world!");
    // Example 2: Using a String
    let greeting = String::from("Welcome to Rust!");
    print_message(greeting);
}