// Welcome to Rustlings! If you're here, that means you've either successfully // downloaded Rustlings, or are looking at this on GitHub. Either way, let me // introduce you to one of the most basic elements of Rust: // // === VARIABLES === // // Variables are essentially little containers that hold, well, something. Think // of them as a little cardboard box that you put stuff into. What can you put // into a virtual cardboard box in Rust? All kinds of stuff, it turns out! // Numbers, words, sequences, and much more. Let's start out simple, though. // Here's our first exercise: pub fn exercise_one() { let x = 5; verify!(0, x, "Number assignment"); // ^ ^ // | | // What's The variable // in it itself } // Did you get all that? The "let" word basically tells us that we now want to // define a variable, and what follows it, the "x" is the name of the variable. // Each variable has a name, like a label you put on your cardboard box so you // don't confuse it with another, similar looking one. // The whole "verify!" deal essentially means that Rustlings is checking if you // solved the exercise correctly. It compares the first argument with the // second, so in this case "0" with "x", where "x" is the _value_ of the variable // we called "x". When you write "x", you pull out the cardboard box labelled "x" // and take out what's inside of it. // Speaking of which, what *is* inside of our "x" cardboard box? I don't think it's // "0"... do you know? Replace the "0" with the value of the variable we defined. // After that, run "cargo run" in your command line, and see if you put in the // right answer. pub fn exec() { exercise_one(); }