# Introduction In this lab, the formatted print functionality in Rust is explained. The `std::fmt` module provides macros such as `format!`, `print!`, `println!`, `eprint!`, and `eprintln!` for handling printing tasks. These macros allow for formatting text with placeholders that are replaced with corresponding arguments. Positional and named arguments can be used, and different formatting can be applied using format characters. The macros also support justifying text, padding numbers, and setting the precision for decimal numbers. The `fmt::Display` trait is used to format text in a user-friendly way, while the `fmt::Debug` trait is used for debugging purposes. Rust also checks for formatting correctness at compile time. Additionally, it is mentioned that implementing the `fmt::Display` trait automatically implements the `ToString` trait, and custom types need to implement the `fmt::Display` trait to be printable. The lab also includes activities to practice using the formatted print macros and traits. > **Note:** If the lab does not specify a file name, you can use any file name you want. For example, you can use `main.rs`, compile and run it with `rustc main.rs && ./main`.
Click the virtual machine below to start practicing