fn main() { // In general, the `{}` will be automatically replaced with any // arguments. These will be stringified. println!("{} days", 31); // Without a suffix, 31 becomes an i32. You can change what type 31 is, // with a suffix. // There are various optional patterns this works with. Positional // arguments can be used. println!("{0}, this is {1}. {1}, this is {0}", "Alice", "Bob"); // As can named arguments. println!("{subject} {verb} {object}", object="the lazy dog", subject="the quick brown fox", verb="jumps over"); // Special formatting can be specified after a `:`. println!("{} of {:b} people know binary, the other half don't", 1, 2); // You can right-align text with a specified width. This will output // " 1". 5 white spaces and a "1". println!("{number:>width$}", number=1, width=6); // You can pad numbers with extra zeroes. This will output "000001". println!("{number:>0width$}", number=1, width=6); // It will even check to make sure the correct number of arguments are // used. println!("My name is {0}, {1} {0}", "Bond"); // FIXME ^ Add the missing argument: "James" // Create a structure which contains an `i32`. Name it `Structure`. struct Structure(i32); // However, custom types such as this structure require more complicated // handling. This will not work. println!("This struct `{}` won't print...", Structure(3)); // FIXME ^ Comment out this line. }