Char Constants

Character constants และ unicode

ASCII Constants

fn main() {
    // ASCII ranges as u8
    const DIGIT_START: u8 = b'0';
    const DIGIT_END: u8 = b'9';
    const UPPER_START: u8 = b'A';
    const UPPER_END: u8 = b'Z';
    const LOWER_START: u8 = b'a';
    const LOWER_END: u8 = b'z';

    println!("=== ASCII Ranges ===");
    println!("Digits: {} - {}", DIGIT_START, DIGIT_END);
    println!("Upper: {} - {}", UPPER_START, UPPER_END);
    println!("Lower: {} - {}", LOWER_START, LOWER_END);

    // Special ASCII
    println!("\n=== Special ASCII ===");
    println!("Space: {}", b' ');
    println!("Tab: {}", b'\t');
    println!("Newline: {}", b'\n');
    println!("Carriage return: {}", b'\r');
    println!("Null: {}", b'\0');

    // Control characters
    println!("\n=== Control ===");
    println!("Bell: {}", 0x07);
    println!("Backspace: {}", 0x08);
    println!("Delete: {}", 0x7F);

    // Check ASCII
    fn is_ascii_digit(c: char) -> bool {
        c.is_ascii_digit()
    }

    fn is_ascii_letter(c: char) -> bool {
        c.is_ascii_alphabetic()
    }

    println!("\n=== Checks ===");
    println!("'5' is digit: {}", is_ascii_digit('5'));
    println!("'A' is letter: {}", is_ascii_letter('A'));
}