Fmt Functions

Formatting functions และ utilities

format_args!

use std::fmt;

fn main() {
    // format_args! creates fmt::Arguments (zero allocation)
    let args = format_args!("Hello, {}!", "world");
    println!("{}", args);

    // Used internally by format!, print!, etc.

    // Passing to functions
    fn log(args: fmt::Arguments) {
        println!("[LOG] {}", args);
    }

    log(format_args!("User {} logged in", "Alice"));
    log(format_args!("Value: {}", 42));

    // With formatting options
    log(format_args!("Float: {:.2}", 3.14159));
    log(format_args!("Padded: {:>10}", "test"));

    // Multiple arguments
    let x = 1;
    let y = 2;
    log(format_args!("{} + {} = {}", x, y, x + y));
}