How to reassign mutable String?

Asked Dec 29 '22 at 00:30

Active Dec 29 '22 at 00:30

Viewed 26 times

Why does reassigning a mutable String results in compile error? Shouldn't mut allow mutating string?

fn main() {
    let mut guess = String::from("foo\n");
    guess = guess.trim();
    println!("Input: {}", guess);
}

Gives

9 |     guess = guess.trim();
  |             ^^^^^^^^^^^^- help: try using a conversion method: `.to_string()`
  |             |
  |             expected struct `String`, found `&str`

asked Dec 29 '22 at 00:30

phoxd

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Trim returns a string slice – Daniel A. White Dec 29 '22 at 00:31
Yes! what would be proper way to trim whitespace and then modify String later? Do you have to recreate new String with `let guess = guess.trim()`? – phoxd Dec 29 '22 at 00:41
1

You cannot assign a string slice to a string, the compiler is correct here, change the line to what it suggests, `guess = guess.trim().to_string();` – Karan Anand Dec 29 '22 at 06:06

How to reassign mutable String?

0 Answers0