Where we print a formatted message
The following needs to be prepared
- A
cargo
created Rust namedprinting
- An editor with the project open
Having setup our Rust environment, it is time we explore the language.
I have used cargo
to create a new project. Lets run it to see we are in a working system. I setup the editor to execute cargo run
on Command-B
. We can see the output below.
The println!
macro has a trick up its sleave. Change the expression to
println!("Hello, {}!", "world");
When we run it we see that println!
can accept an argument. The argument "world"
is replaced with the placeholder {}
, sometimes called a mustache pair.
println!
can accept multiple arguments. For example
println!("{}, {}!", "Hello", "world");
works just as well.
And there you have it, we printed a formatted message