// ./src/std/str.md fn part0() { // (all the type annotations are superfluous) // A reference to a string allocated in read only memory let pangram: &'static str = "the quick brown fox jumps over the lazy dog"; println!("Pangram: {}", pangram); // Iterate over words in reverse, no new string is allocated println!("Words in reverse"); for word in pangram.split_whitespace().rev() { println!("> {}", word); } // Copy chars into a vector, sort and remove duplicates let mut chars: Vec = pangram.chars().collect(); chars.sort(); chars.dedup(); // Create an empty and growable `String` let mut string = String::new(); for c in chars { // Insert a char at the end of string string.push(c); // Insert a string at the end of string string.push_str(", "); } // The trimmed string is a slice to the original string, hence no new // allocation is performed let chars_to_trim: &[char] = &[' ', ',']; let trimmed_str: &str = string.trim_matches(chars_to_trim); println!("Used characters: {}", trimmed_str); // Heap allocate a string let alice = String::from("I like dogs"); // Allocate new memory and store the modified string there let bob: String = alice.replace("dog", "cat"); println!("Alice says: {}", alice); println!("Bob says: {}", bob); } fn part1() { // You can use escapes to write bytes by their hexadecimal values... let byte_escape = "I'm writing \x52\x75\x73\x74!"; println!("What are you doing\x3F (\\x3F means ?) {}", byte_escape); // ...or Unicode code points. let unicode_codepoint = "\u{211D}"; let character_name = "\"DOUBLE-STRUCK CAPITAL R\""; println!("Unicode character {} (U+211D) is called {}", unicode_codepoint, character_name ); let long_string = "String literals can span multiple lines. The linebreak and indentation here ->\ <- can be escaped too!"; println!("{}", long_string); } pub fn main() { part0(); part1(); }