Pointer Functions

Raw pointer operations

ptr::null และ ptr::null_mut

use std::ptr;

fn main() {
    // Create null pointers
    let null_const: *const i32 = ptr::null();
    let null_mut: *mut i32 = ptr::null_mut();

    println!("=== Null Pointers ===");
    println!("null(): {:?}", null_const);
    println!("null_mut(): {:?}", null_mut);

    // Check for null
    println!("\nis_null(): {}", null_const.is_null());

    // Can also use std::ptr::null::<T>()
    let null_str: *const str = ptr::null();
    println!("null str ptr: {:?}", null_str);

    // NonNull for non-null pointers
    use std::ptr::NonNull;

    let mut value = 42;
    let non_null = NonNull::new(&mut value).unwrap();
    println!("\nNonNull: {:?}", non_null);

    // NonNull from dangling
    let dangling: NonNull<i32> = NonNull::dangling();
    println!("Dangling: {:?}", dangling);
}