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What is String

• There is only one String type in Rust's core language, and that is String slice.strUsually regarded as&strborrowing.
• The String type is provided through the standard library rather than being coded directly into the core language; it is a growable, mutable, UTF-8-encoded type.
• strandStringThey are all utf-8 encoded.

Creating a New String

• String is actually implemented by wrapping a vector of bytes type.
• Use the new method to create a String:let mut s = String::new()
• Use the to_string method to create a String:

  let data = "initial contents";
  let s = data.to_string();
  let s = "initial contents".to_string();
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• Use the String::from method to create a string.let s = String::from("initial contents").

Update String

Appending strings using push_str and push

let mut s = String::from("foo");
s.push_str("bar");
// s is foobar
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push_strThis method does not change the ownership of the string.

let mut s = String::from("lo");
s.push('l');
// s is lol
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Concatenate strings using the + operator or the format! macro

let s1 = String::from("Hello, ");
let s2 = String::from("world!");
let s3 = s1 + &s2; // note s1 has been moved here and can no longer be used
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let s1 = String::from("tic");
let s2 = String::from("tac");
let s3 = String::from("toe");

let s = format!("{s1}-{s2}-{s3}");
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Rust does not allow subscripting of individual characters in a string.

Methods for iterating over strings

• You can access individual Unicode characters using the chars method and access each byte using the bytes method.

for c in "Зд".chars() {
    println!("{c}");
}
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