mirror of
https://github.com/rust-lang/rustlings.git
synced 2024-12-04 10:35:06 +02:00
feat: Refactor hint system
Hints are now accessible using the CLI subcommand `rustlings hint <exercise name`. BREAKING CHANGE: This fundamentally changes the way people interact with exercises.
This commit is contained in:
parent
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@ -1,5 +1,5 @@
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// enums1.rs
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// Make me compile! Scroll down for hints!
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// Make me compile! Execute `rustlings hint enums1` for hints!
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#[derive(Debug)]
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enum Message {
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@ -12,31 +12,3 @@ fn main() {
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println!("{:?}", Message::Move);
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println!("{:?}", Message::ChangeColor);
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}
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// Hint: The declaration of the enumeration type has not been defined yet.
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@ -1,5 +1,5 @@
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// enums2.rs
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// Make me compile! Scroll down for hints
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// Make me compile! Execute `rustlings hint enums2` for hints!
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#[derive(Debug)]
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enum Message {
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@ -24,38 +24,3 @@ fn main() {
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message.call();
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}
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}
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// Hint: you can create enumerations that have different variants with different types
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// such as no data, anonymous structs, a single string, tuples, ...etc
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@ -4,7 +4,7 @@
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// was, instead of just sometimes returning `None`. The 2nd test currently
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// does not compile or pass, but it illustrates the behavior we would like
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// this function to have.
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// Scroll down for hints!!!
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// Execute `rustlings hint errors1` for hints!
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pub fn generate_nametag_text(name: String) -> Option<String> {
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if name.len() > 0 {
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@ -38,36 +38,3 @@ mod tests {
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);
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}
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}
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// `Err` is one of the variants of `Result`, so what the 2nd test is saying
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// is that `generate_nametag_text` should return a `Result` instead of an
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// `Option`.
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// To make this change, you'll need to:
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// - update the return type in the function signature to be a Result<String, String> that
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// could be the variants `Ok(String)` and `Err(String)`
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// - change the body of the function to return `Ok(stuff)` where it currently
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// returns `Some(stuff)`
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// - change the body of the function to return `Err(error message)` where it
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// currently returns `None`
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// - change the first test to expect `Ok(stuff)` where it currently expects
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// `Some(stuff)`.
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@ -14,7 +14,7 @@
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// and add.
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// There are at least two ways to implement this that are both correct-- but
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// one is a lot shorter! Scroll down for hints to both ways.
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// one is a lot shorter! Execute `rustlings hint errors2` for hints to both ways.
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use std::num::ParseIntError;
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@ -43,27 +43,3 @@ mod tests {
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);
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}
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}
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// One way to handle this is using a `match` statement on
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// `item_quantity.parse::<i32>()` where the cases are `Ok(something)` and
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// `Err(something)`. This pattern is very common in Rust, though, so there's
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// a `?` operator that does pretty much what you would make that match statement
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// do for you! Take a look at this section of the Error Handling chapter:
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// https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
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// and give it a try!
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// errors3.rs
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// This is a program that is trying to use a completed version of the
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// `total_cost` function from the previous exercise. It's not working though!
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// Why not? What should we do to fix it? Scroll for hints!
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// Why not? What should we do to fix it?
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// Execute `rustlings hint errors3` for hints!
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use std::num::ParseIntError;
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@ -26,22 +27,3 @@ pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
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Ok(qty * cost_per_item + processing_fee)
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}
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// If other functions can return a `Result`, why shouldn't `main`?
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@ -13,7 +13,7 @@
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// type goes where the question marks are, and how do we return
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// that type from the body of read_and_validate?
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//
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// Scroll down for hints :)
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// Execute `rustlings hint errors4` for hints :)
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use std::error;
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use std::fmt;
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@ -110,138 +110,3 @@ impl error::Error for CreationError {
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}
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}
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}
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// First hint: To figure out what type should go where the ??? is, take a look
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// at the test helper function `test_with_str`, since it returns whatever
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// `read_and_validate` returns and`test_with_str` has its signature fully
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// specified.
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// Next hint: There are three places in `read_and_validate` that we call a
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// function that returns a `Result` (that is, the functions might fail).
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// Apply the `?` operator on those calls so that we return immediately from
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// `read_and_validate` if those function calls fail.
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// Another hint: under the hood, the `?` operator calls `From::from`
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// on the error value to convert it to a boxed trait object, a Box<dyn error::Error>,
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// which is polymorphic-- that means that lots of different kinds of errors
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// can be returned from the same function because all errors act the same
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// since they all implement the `error::Error` trait.
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// Check out this section of the book:
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// https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
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// Another another hint: Note that because the `?` operator returns
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// the *unwrapped* value in the `Ok` case, if we want to return a `Result` from
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// `read_and_validate` for *its* success case, we'll have to rewrap a value
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// that we got from the return value of a `?`ed call in an `Ok`-- this will
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// look like `Ok(something)`.
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// Another another another hint: `Result`s must be "used", that is, you'll
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// get a warning if you don't handle a `Result` that you get in your
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// function. Read more about that in the `std::result` module docs:
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// https://doc.rust-lang.org/std/result/#results-must-be-used
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// This example panics because the second time it calls `pop`, the `vec`
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// is empty, so `pop` returns `None`, and `unwrap` panics if it's called
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// on `None`. Handle this in a more graceful way than calling `unwrap`!
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// Scroll down for hints :)
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// Execute `rustlings hint option1` for hints :)
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pub fn pop_too_much() -> bool {
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let mut list = vec![3];
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assert!(pop_too_much());
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}
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}
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// Try using a `match` statement where the arms are `Some(thing)` and `None`.
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// Or set a default value to print out if you get `None` by using the
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// function `unwrap_or`.
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// Or use an `if let` statement on the result of `pop()` to both destructure
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// a `Some` value and only print out something if we have a value!
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// result1.rs
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// Make this test pass! Scroll down for hints :)
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// Make this test pass! Execute `rustlings hint option2` for hints :)
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#[derive(PartialEq, Debug)]
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struct PositiveNonzeroInteger(u64);
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assert_eq!(Err(CreationError::Zero), PositiveNonzeroInteger::new(0));
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}
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// `PositiveNonzeroInteger::new` is always creating a new instance and returning an `Ok` result.
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// It should be doing some checking, returning an `Err` result if those checks fail, and only
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// returning an `Ok` result if those checks determine that everything is... okay :)
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// functions1.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint function1` for hints :)
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fn main() {
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call_me();
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}
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// This main function is calling a function that it expects to exist, but the
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// function doesn't exist. It expects this function to have the name `call_me`.
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// It expects this function to not take any arguments and not return a value.
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// Sounds a lot like `main`, doesn't it?
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// functions2.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint functions2` for hints :)
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fn main() {
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call_me(3);
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@ -10,33 +10,3 @@ fn call_me(num) {
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println!("Ring! Call number {}", i + 1);
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}
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}
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// Rust requires that all parts of a function's signature have type annotations,
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// but `call_me` is missing the type annotation of `num`.
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// functions3.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint functions3` for hints :)
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fn main() {
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call_me();
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println!("Ring! Call number {}", i + 1);
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}
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}
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// This time, the function *declaration* is okay, but there's something wrong
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// with the place where we're calling the function.
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// functions4.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint functions4` for hints :)
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// This store is having a sale where if the price is an even number, you get
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// 10 (money unit) off, but if it's an odd number, it's 3 (money unit) less.
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fn is_even(num: i32) -> bool {
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num % 2 == 0
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}
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// The error message points to line 12 and says it expects a type after the
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// `->`. This is where the function's return type should be-- take a look at
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// the `is_even` function for an example!
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// functions5.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint functions5` for hints :)
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fn main() {
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let answer = square(3);
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fn square(num: i32) -> i32 {
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num * num;
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}
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// This is a really common error that can be fixed by removing one character.
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// It happens because Rust distinguishes between expressions and statements: expressions return
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// a value based on its operand, and statements simply return a () type which behaves just like `void` in C/C++ language.
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// We want to return a value of `i32` type from the `square` function, but it is returning a `()` type...
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// They are not the same. There are two solutions:
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// 1. Add a `return` ahead of `num * num;`
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// 2. remove `;`, make it to be `num * num`
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// Do not use:
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// - another function call
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// - additional variables
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// Scroll down for hints.
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// Execute `rustlings hint if1` for hints
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}
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// Don't mind this for now :)
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@ -23,36 +23,3 @@ mod tests {
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assert_eq!(42, bigger(32, 42));
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}
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}
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// It's possible to do this in one line if you would like!
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// Some similar examples from other languages:
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// - In C(++) this would be: `a > b ? a : b`
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// - In Python this would be: `a if a > b else b`
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// Remember in Rust that:
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// - the `if` condition does not need to be surrounded by parentheses
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// - `if`/`else` conditionals are expressions
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// - Each condition is followed by a `{}` block.
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// macros1.rs
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// Make me compile! Scroll down for hints :)
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// Make me compile! Execute `rustlings hint macros1` for hints :)
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macro_rules! my_macro {
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() => {
|
||||
@ -10,55 +10,3 @@ macro_rules! my_macro {
|
||||
fn main() {
|
||||
my_macro();
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// When you call a macro, you need to add something special compared to a
|
||||
// regular function call. If you're stuck, take a look at what's inside
|
||||
// `my_macro`.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// macros2.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute `rustlings hint macros2` for hints :)
|
||||
|
||||
fn main() {
|
||||
my_macro!();
|
||||
@ -10,64 +10,3 @@ macro_rules! my_macro {
|
||||
println!("Check out my macro!");
|
||||
};
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Macros don't quite play by the same rules as the rest of Rust, in terms of
|
||||
// what's available where.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Unlike other things in Rust, the order of "where you define a macro" versus
|
||||
// "where you use it" actually matters.
|
||||
|
@ -1,5 +1,6 @@
|
||||
// macros3.rs
|
||||
// Make me compile, without taking the macro out of the module! Scroll down for hints :)
|
||||
// Make me compile, without taking the macro out of the module!
|
||||
// Execute `rustlings hint macros3` for hints :)
|
||||
|
||||
mod macros {
|
||||
macro_rules! my_macro {
|
||||
@ -12,64 +13,3 @@ mod macros {
|
||||
fn main() {
|
||||
my_macro!();
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// In order to use a macro outside of its module, you need to do something
|
||||
// special to the module to lift the macro out into its parent.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The same trick also works on "extern crate" statements for crates that have
|
||||
// exported macros, if you've seen any of those around.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// macros4.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute `rustlings hint macros4` for hints :)
|
||||
|
||||
macro_rules! my_macro {
|
||||
() => {
|
||||
@ -14,64 +14,3 @@ fn main() {
|
||||
my_macro!();
|
||||
my_macro!(7777);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// You only need to add a single character to make this compile.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The way macros are written, it wants to see something between each
|
||||
// "macro arm", so it can separate them.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// modules1.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute `rustlings hint modules1` for hints :)
|
||||
|
||||
mod sausage_factory {
|
||||
fn make_sausage() {
|
||||
@ -10,34 +10,3 @@ mod sausage_factory {
|
||||
fn main() {
|
||||
sausage_factory::make_sausage();
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Everything is private in Rust by default-- but there's a keyword we can use
|
||||
// to make something public! The compiler error should point to the thing that
|
||||
// needs to be public.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// modules2.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute `rustlings hint modules2` for hints :)
|
||||
|
||||
mod delicious_snacks {
|
||||
use self::fruits::PEAR as fruit;
|
||||
@ -23,25 +23,3 @@ fn main() {
|
||||
delicious_snacks::veggie
|
||||
);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The delicious_snacks module is trying to present an external
|
||||
// interface (the `fruit` and `veggie` constants) that is different than
|
||||
// its internal structure (the `fruits` and `veggies` modules and
|
||||
// associated constants). It's almost there except for one keyword missing for
|
||||
// each constant.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// move_semantics1.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute `rustlings hint move_semantics1` for hints :)
|
||||
|
||||
fn main() {
|
||||
let vec0 = Vec::new();
|
||||
@ -22,21 +22,3 @@ fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
|
||||
|
||||
vec
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// So you've got the "cannot borrow immutable local variable `vec1` as mutable" error on line 11,
|
||||
// right? The fix for this is going to be adding one keyword, and the addition is NOT on line 11
|
||||
// where the error is.
|
||||
|
@ -1,5 +1,6 @@
|
||||
// move_semantics2.rs
|
||||
// Make me compile without changing line 10! Scroll down for hints :)
|
||||
// Make me compile without changing line 10!
|
||||
// Execute `rustlings hint move_semantics2` for hints :)
|
||||
|
||||
fn main() {
|
||||
let vec0 = Vec::new();
|
||||
@ -23,31 +24,3 @@ fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
|
||||
|
||||
vec
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// So `vec0` is being *moved* into the function `fill_vec` when we call it on
|
||||
// line 7, which means it gets dropped at the end of `fill_vec`, which means we
|
||||
// can't use `vec0` again on line 10 (or anywhere else in `main` after the
|
||||
// `fill_vec` call for that matter). We could fix this in a few ways, try them
|
||||
// all!
|
||||
// 1. Make another, separate version of the data that's in `vec0` and pass that
|
||||
// to `fill_vec` instead.
|
||||
// 2. Make `fill_vec` borrow its argument instead of taking ownership of it,
|
||||
// and then copy the data within the function in order to return an owned
|
||||
// `Vec<i32>`
|
||||
// 3. Make `fill_vec` *mutably* borrow its argument (which will need to be
|
||||
// mutable), modify it directly, then not return anything. Then you can get rid
|
||||
// of `vec1` entirely -- note that this will change what gets printed by the
|
||||
// first `println!`
|
||||
|
@ -1,7 +1,7 @@
|
||||
// move_semantics3.rs
|
||||
// Make me compile without adding new lines-- just changing existing lines!
|
||||
// (no lines with multiple semicolons necessary!)
|
||||
// Scroll down for hints :)
|
||||
// Execute `rustlings hint move_semantics3` for hints :)
|
||||
|
||||
fn main() {
|
||||
let vec0 = Vec::new();
|
||||
@ -22,24 +22,3 @@ fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
|
||||
|
||||
vec
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The difference between this one and the previous ones is that the first line
|
||||
// of `fn fill_vec` that had `let mut vec = vec;` is no longer there. You can,
|
||||
// instead of adding that line back, add `mut` in one place that will change
|
||||
// an existing binding to be a mutable binding instead of an immutable one :)
|
||||
|
@ -1,7 +1,8 @@
|
||||
// move_semantics4.rs
|
||||
// Refactor this code so that instead of having `vec0` and creating the vector
|
||||
// in `fn main`, we instead create it within `fn fill_vec` and transfer the
|
||||
// freshly created vector from fill_vec to its caller. Scroll for hints!
|
||||
// freshly created vector from fill_vec to its caller.
|
||||
// Execute `rustlings hint move_semantics4` for hints!
|
||||
|
||||
fn main() {
|
||||
let vec0 = Vec::new();
|
||||
@ -25,24 +26,3 @@ fn fill_vec() -> Vec<i32> {
|
||||
|
||||
vec
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Stop reading whenever you feel like you have enough direction :) Or try
|
||||
// doing one step and then fixing the compiler errors that result!
|
||||
// So the end goal is to:
|
||||
// - get rid of the first line in main that creates the new vector
|
||||
// - so then `vec0` doesn't exist, so we can't pass it to `fill_vec`
|
||||
// - we don't want to pass anything to `fill_vec`, so its signature should
|
||||
// reflect that it does not take any arguments
|
||||
// - since we're not creating a new vec in `main` anymore, we need to create
|
||||
// a new vec in `fill_vec`, similarly to the way we did in `main`
|
||||
|
@ -1,6 +1,6 @@
|
||||
// primitive_types3.rs
|
||||
// Create an array with at least 100 elements in it where the ??? is.
|
||||
// Scroll down for hints!
|
||||
// Execute `rustlings hint primitive_types3` for hints!
|
||||
|
||||
fn main() {
|
||||
let a = ???
|
||||
@ -11,37 +11,3 @@ fn main() {
|
||||
println!("Meh, I eat arrays like that for breakfast.");
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// There's a shorthand to initialize Arrays with a certain size that does not
|
||||
// require you to type in 100 items (but you certainly can if you want!).
|
||||
// For example, you can do:
|
||||
// let array = ["Are we there yet?"; 10];
|
||||
|
||||
// Bonus: what are some other things you could have that would return true
|
||||
// for `a.len() >= 100`?
|
||||
|
@ -1,6 +1,6 @@
|
||||
// primitive_types4.rs
|
||||
// Get a slice out of Array a where the ??? is so that the `if` statement
|
||||
// returns true. Scroll down for hints!!
|
||||
// returns true. Execute `rustlings hint primitive_types4` for hints!!
|
||||
|
||||
#[test]
|
||||
fn main() {
|
||||
@ -10,59 +10,3 @@ fn main() {
|
||||
|
||||
assert_eq!([2, 3, 4], nice_slice)
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Take a look at the Understanding Ownership -> Slices -> Other Slices section of the book:
|
||||
// https://doc.rust-lang.org/book/ch04-03-slices.html
|
||||
// and use the starting and ending indices of the items in the Array
|
||||
// that you want to end up in the slice.
|
||||
|
||||
// If you're curious why the right hand of the `==` comparison does not
|
||||
// have an ampersand for a reference since the left hand side is a
|
||||
// reference, take a look at the Deref coercions section of the book:
|
||||
// https://doc.rust-lang.org/book/ch15-02-deref.html
|
||||
|
@ -1,6 +1,6 @@
|
||||
// primitive_types5.rs
|
||||
// Destructure the `cat` tuple so that the println will work.
|
||||
// Scroll down for hints!
|
||||
// Execute `rustlings hint primitive_types5` for hints!
|
||||
|
||||
fn main() {
|
||||
let cat = ("Furry McFurson", 3.5);
|
||||
@ -8,38 +8,3 @@ fn main() {
|
||||
|
||||
println!("{} is {} years old.", name, age);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Take a look at the Data Types -> The Tuple Type section of the book:
|
||||
// https://doc.rust-lang.org/book/ch03-02-data-types.html#the-tuple-type
|
||||
// Particularly the part about destructuring (second to last example in the section).
|
||||
// You'll need to make a pattern to bind `name` and `age` to the appropriate parts
|
||||
// of the tuple. You can do it!!
|
||||
|
@ -1,45 +1,9 @@
|
||||
// primitive_types6.rs
|
||||
// Use a tuple index to access the second element of `numbers`.
|
||||
// You can put this right into the `println!` where the ??? is.
|
||||
// Scroll down for hints!
|
||||
// Execute `rustlings hint primitive_types6` for hints!
|
||||
|
||||
fn main() {
|
||||
let numbers = (1, 2, 3);
|
||||
println!("The second number is {}", ???);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// While you could use a destructuring `let` for the tuple here, try
|
||||
// indexing into it instead, as explained in the last example of the
|
||||
// Data Types -> The Tuple Type section of the book:
|
||||
// https://doc.rust-lang.org/book/ch03-02-data-types.html#the-tuple-type
|
||||
// Now you have another tool in your toolbox!
|
||||
|
@ -2,7 +2,7 @@
|
||||
// Make this code compile by filling in a value for `shared_numbers` where the
|
||||
// TODO comment is and creating an initial binding for `child_numbers`
|
||||
// somewhere. Try not to create any copies of the `numbers` Vec!
|
||||
// Scroll down for hints :)
|
||||
// Execute `rustlings help arc1` for hints :)
|
||||
|
||||
use std::sync::Arc;
|
||||
use std::thread;
|
||||
@ -27,29 +27,3 @@ fn main() {
|
||||
handle.join().unwrap();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Make `shared_numbers` be an `Arc` from the numbers vector. Then, in order
|
||||
// to avoid creating a copy of `numbers`, you'll need to create `child_numbers`
|
||||
// inside the loop but still in the main thread.
|
||||
|
||||
// `child_numbers` should be a clone of the Arc of the numbers instead of a
|
||||
// thread-local copy of the numbers.
|
||||
|
@ -3,7 +3,7 @@
|
||||
// Step 1. Complete the `capitalize_first` function to pass the first two cases
|
||||
// Step 2. Apply the `capitalize_first` function to a vector of strings, ensuring that it returns a vector of strings as well
|
||||
// Step 3. Apply the `capitalize_first` function again to a list, but try and ensure it returns a single string
|
||||
// As always, there are hints below!
|
||||
// As always, there are hints if you execute `rustlings hint iterators2`!
|
||||
|
||||
pub fn capitalize_first(input: &str) -> String {
|
||||
let mut c = input.chars();
|
||||
@ -44,102 +44,3 @@ mod tests {
|
||||
assert_eq!(capitalized_words, "Hello World");
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Step 1
|
||||
// You need to call something on `first` before it can be collected
|
||||
// Currently its type is `char`. Have a look at the methods that are available on that type:
|
||||
// https://doc.rust-lang.org/std/primitive.char.html
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Step 2
|
||||
// First you'll need to turn the Vec into an iterator
|
||||
// Then you'll need to apply your function unto each item in the vector
|
||||
// P.s. Don't forget to collect() at the end!
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Step 3.
|
||||
// This is very similar to the previous test. The only real change is that you will need to
|
||||
// alter the type that collect is coerced into. For a bonus you could try doing this with a
|
||||
// turbofish
|
||||
|
@ -4,8 +4,7 @@
|
||||
// 1. Complete the divide function to get the first four tests to pass
|
||||
// 2. Uncomment the last two tests and get them to pass by filling in
|
||||
// values for `x` using `division_results`.
|
||||
// Scroll down for a minor hint for part 2, and scroll down further for
|
||||
// a major hint.
|
||||
// Execute `rustlings hint iterators3` to get some hints!
|
||||
// Have fun :-)
|
||||
|
||||
#[derive(Debug, PartialEq, Eq)]
|
||||
@ -75,72 +74,3 @@ mod tests {
|
||||
}
|
||||
*/
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Minor hint: In each of the two cases in the match in main, you can create x with either
|
||||
// a 'turbofish' or by hinting the type of x to the compiler. You may try both.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Major hint: Have a look at the Iter trait and at the explanation of its collect function.
|
||||
// Especially the part about Result is interesting.
|
||||
|
@ -9,7 +9,7 @@ pub fn factorial(num: u64) -> u64 {
|
||||
// - additional variables
|
||||
// For the most fun don't use:
|
||||
// - recursion
|
||||
// Scroll down for hints.
|
||||
// Execute `rustlings hint iterators4` for hints.
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
@ -30,32 +30,3 @@ mod tests {
|
||||
assert_eq!(24, factorial(4));
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// In an imperative language you might write a for loop to iterate through
|
||||
// multiply the values into a mutable variable. Or you might write code more
|
||||
// functionally with recursion and a match clause. But you can also use ranges
|
||||
// and iterators to solve this in rust.
|
||||
|
@ -1,5 +1,6 @@
|
||||
// strings1.rs
|
||||
// Make me compile without changing the function signature! Scroll down for hints :)
|
||||
// Make me compile without changing the function signature!
|
||||
// Execute `rustlings hint strings1` for hints ;)
|
||||
|
||||
fn main() {
|
||||
let answer = current_favorite_color();
|
||||
@ -9,38 +10,3 @@ fn main() {
|
||||
fn current_favorite_color() -> String {
|
||||
"blue"
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The `current_favorite_color` function is currently returning a string slice with the `'static`
|
||||
// lifetime. We know this because the data of the string lives in our code itself -- it doesn't
|
||||
// come from a file or user input or another program -- so it will live as long as our program
|
||||
// lives. But it is still a string slice. There's one way to create a `String` by converting a
|
||||
// string slice covered in the Strings chapter of the book, and another way that uses the `From`
|
||||
// trait.
|
||||
|
@ -1,5 +1,6 @@
|
||||
// strings2.rs
|
||||
// Make me compile without changing the function signature! Scroll down for hints :)
|
||||
// Make me compile without changing the function signature!
|
||||
// Execute `rustlings hint strings2` for hints :)
|
||||
|
||||
fn main() {
|
||||
let word = String::from("green"); // Try not changing this line :)
|
||||
@ -13,32 +14,3 @@ fn main() {
|
||||
fn is_a_color_word(attempt: &str) -> bool {
|
||||
attempt == "green" || attempt == "blue" || attempt == "red"
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Yes, it would be really easy to fix this by just changing the value bound to `word` to be a
|
||||
// string slice instead of a `String`, wouldn't it?? There is a way to add one character to line
|
||||
// 6, though, that will coerce the `String` into a string slice.
|
||||
|
@ -4,7 +4,7 @@
|
||||
// rustlings run --test exercises/tests/tests1.rs
|
||||
|
||||
// This test has a problem with it -- make the test compile! Make the test
|
||||
// pass! Make the test fail! Scroll down for hints :)
|
||||
// pass! Make the test fail! Execute `rustlings hint tests1` for hints :)
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
@ -13,37 +13,3 @@ mod tests {
|
||||
assert!();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// You don't even need to write any code to test -- you can just test values and run that, even
|
||||
// though you wouldn't do that in real life :) `assert!` is a macro that needs an argument.
|
||||
// Depending on the value of the argument, `assert!` will do nothing (in which case the test will
|
||||
// pass) or `assert!` will panic (in which case the test will fail). So try giving different values
|
||||
// to `assert!` and see which ones compile, which ones pass, and which ones fail :)
|
||||
|
@ -1,6 +1,6 @@
|
||||
// tests2.rs
|
||||
// This test has a problem with it -- make the test compile! Make the test
|
||||
// pass! Make the test fail! Scroll down for hints :)
|
||||
// pass! Make the test fail! Execute `rustlings hint tests2` for hints :)
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
@ -9,36 +9,3 @@ mod tests {
|
||||
assert_eq!();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Like the previous exercise, you don't need to write any code to get this test to compile and
|
||||
// run. `assert_eq!` is a macro that takes two arguments and compares them. Try giving it two
|
||||
// values that are equal! Try giving it two arguments that are different! Try giving it two values
|
||||
// that are of different types! Try switching which argument comes first and which comes second!
|
||||
|
@ -1,7 +1,8 @@
|
||||
// tests3.rs
|
||||
// This test isn't testing our function -- make it do that in such a way that
|
||||
// the test passes. Then write a second test that tests whether we get the result
|
||||
// we expect to get when we call `is_even(5)`. Scroll down for hints!
|
||||
// we expect to get when we call `is_even(5)`.
|
||||
// Execute `rustlings hint tests3` for hints :)
|
||||
|
||||
pub fn is_even(num: i32) -> bool {
|
||||
num % 2 == 0
|
||||
@ -16,28 +17,3 @@ mod tests {
|
||||
assert!();
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// You can call a function right where you're passing arguments to `assert!` -- so you could do
|
||||
// something like `assert!(having_fun())`. If you want to check that you indeed get false, you
|
||||
// can negate the result of what you're doing using `!`, like `assert!(!having_fun())`.
|
||||
|
@ -1,8 +1,8 @@
|
||||
// threads1.rs
|
||||
// Make this compile! Scroll down for hints :) The idea is the thread
|
||||
// spawned on line 19 is completing jobs while the main thread is
|
||||
// Make this compile! Execute `rustlings hint threads1` for hints :)
|
||||
// The idea is the thread spawned on line 19 is completing jobs while the main thread is
|
||||
// monitoring progress until 10 jobs are completed. If you see 6 lines
|
||||
// of "waiting..." and the program ends without timing out the playground,
|
||||
// of "waiting..." and the program ends without timing out when running,
|
||||
// you've got it :)
|
||||
|
||||
use std::sync::Arc;
|
||||
@ -27,69 +27,3 @@ fn main() {
|
||||
thread::sleep(Duration::from_millis(500));
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// `Arc` is an Atomic Reference Counted pointer that allows safe, shared access
|
||||
// to **immutable** data. But we want to *change* the number of `jobs_completed`
|
||||
// so we'll need to also use another type that will only allow one thread to
|
||||
// mutate the data at a time. Take a look at this section of the book:
|
||||
// https://doc.rust-lang.org/book/ch16-03-shared-state.html#atomic-reference-counting-with-arct
|
||||
// and keep scrolling if you'd like more hints :)
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Do you now have an `Arc` `Mutex` `JobStatus` at the beginning of main? Like:
|
||||
// `let status = Arc::new(Mutex::new(JobStatus { jobs_completed: 0 }));`
|
||||
// Similar to the code in the example in the book that happens after the text
|
||||
// that says "We can use Arc<T> to fix this.". If not, give that a try! If you
|
||||
// do and would like more hints, keep scrolling!!
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Make sure neither of your threads are holding onto the lock of the mutex
|
||||
// while they are sleeping, since this will prevent the other thread from
|
||||
// being allowed to get the lock. Locks are automatically released when
|
||||
// they go out of scope.
|
||||
|
||||
// Ok, so, real talk, this was actually tricky for *me* to do too. And
|
||||
// I could see a lot of different problems you might run into, so at this
|
||||
// point I'm not sure which one you've hit :) Please see a few possible
|
||||
// answers on https://github.com/carols10cents/rustlings/issues/3 --
|
||||
// mine is a little more complicated because I decided I wanted to see
|
||||
// the number of jobs currently done when I was checking the status.
|
||||
|
||||
// Please open an issue if you're still running into a problem that
|
||||
// these hints are not helping you with, or if you've looked at the sample
|
||||
// answers and don't understand why they work and yours doesn't.
|
||||
|
||||
// If you've learned from the sample solutions, I encourage you to come
|
||||
// back to this exercise and try it again in a few days to reinforce
|
||||
// what you've learned :)
|
||||
|
@ -1,42 +1,7 @@
|
||||
// variables1.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute the command `rustlings hint variables1` if you want a hint :)
|
||||
|
||||
fn main() {
|
||||
x = 5;
|
||||
println!("x has the value {}", x);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Hint: The declaration on line 5 is missing a keyword that is needed in Rust
|
||||
// to create a new variable binding.
|
||||
|
@ -1,5 +1,5 @@
|
||||
// variables2.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute the command `rustlings hint variables2` if you want a hint :)
|
||||
|
||||
fn main() {
|
||||
let x;
|
||||
@ -9,39 +9,3 @@ fn main() {
|
||||
println!("Not ten!");
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// The compiler message is saying that Rust cannot infer the type that the
|
||||
// variable binding `x` has with what is given here.
|
||||
// What happens if you annotate line 5 with a type annotation?
|
||||
// What if you give x a value?
|
||||
// What if you do both?
|
||||
// What type should x be, anyway?
|
||||
// What if x is the same type as 10? What if it's a different type?
|
||||
|
@ -1,5 +1,5 @@
|
||||
// variables3.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute the command `rustlings hint variables3` if you want a hint :)
|
||||
|
||||
fn main() {
|
||||
let x = 3;
|
||||
@ -7,37 +7,3 @@ fn main() {
|
||||
x = 5;
|
||||
println!("Number {}", x);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// In Rust, variable bindings are immutable by default. But here we're trying
|
||||
// to reassign a different value to x! There's a keyword we can use to make
|
||||
// a variable binding mutable instead.
|
||||
|
@ -1,45 +1,7 @@
|
||||
// variables4.rs
|
||||
// Make me compile! Scroll down for hints :)
|
||||
// Make me compile! Execute the command `rustlings hint variables4` if you want a hint :)
|
||||
|
||||
fn main() {
|
||||
let x: i32;
|
||||
println!("Number {}", x);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
// Oops! In this exercise, we have a variable binding that we've created on
|
||||
// line 5, and we're trying to use it on line 6, but we haven't given it a
|
||||
// value. We can't print out something that isn't there; try giving x a value!
|
||||
// This is an error that can cause bugs that's very easy to make in any
|
||||
// programming language -- thankfully the Rust compiler has caught this for us!
|
||||
|
324
info.toml
324
info.toml
@ -4,21 +4,42 @@
|
||||
name = "variables1"
|
||||
path = "exercises/variables/variables1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Hint: The declaration on line 5 is missing a keyword that is needed in Rust
|
||||
to create a new variable binding."""
|
||||
|
||||
[[exercises]]
|
||||
name = "variables2"
|
||||
path = "exercises/variables/variables2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
The compiler message is saying that Rust cannot infer the type that the
|
||||
variable binding `x` has with what is given here.
|
||||
What happens if you annotate line 5 with a type annotation?
|
||||
What if you give x a value?
|
||||
What if you do both?
|
||||
What type should x be, anyway?
|
||||
What if x is the same type as 10? What if it's a different type?"""
|
||||
|
||||
[[exercises]]
|
||||
name = "variables3"
|
||||
path = "exercises/variables/variables3.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
In Rust, variable bindings are immutable by default. But here we're trying
|
||||
to reassign a different value to x! There's a keyword we can use to make
|
||||
a variable binding mutable instead."""
|
||||
|
||||
[[exercises]]
|
||||
name = "variables4"
|
||||
path = "exercises/variables/variables4.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Oops! In this exercise, we have a variable binding that we've created on
|
||||
line 5, and we're trying to use it on line 6, but we haven't given it a
|
||||
value. We can't print out something that isn't there; try giving x a value!
|
||||
This is an error that can cause bugs that's very easy to make in any
|
||||
programming language -- thankfully the Rust compiler has caught this for us!"""
|
||||
|
||||
# IF
|
||||
|
||||
@ -26,6 +47,15 @@ mode = "compile"
|
||||
name = "if1"
|
||||
path = "exercises/if/if1.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
It's possible to do this in one line if you would like!
|
||||
Some similar examples from other languages:
|
||||
- In C(++) this would be: `a > b ? a : b`
|
||||
- In Python this would be: `a if a > b else b`
|
||||
Remember in Rust that:
|
||||
- the `if` condition does not need to be surrounded by parentheses
|
||||
- `if`/`else` conditionals are expressions
|
||||
- Each condition is followed by a `{}` block."""
|
||||
|
||||
# FUNCTIONS
|
||||
|
||||
@ -33,26 +63,50 @@ mode = "test"
|
||||
name = "functions1"
|
||||
path = "exercises/functions/functions1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
This main function is calling a function that it expects to exist, but the
|
||||
function doesn't exist. It expects this function to have the name `call_me`.
|
||||
It expects this function to not take any arguments and not return a value.
|
||||
Sounds a lot like `main`, doesn't it?"""
|
||||
|
||||
[[exercises]]
|
||||
name = "functions2"
|
||||
path = "exercises/functions/functions2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Rust requires that all parts of a function's signature have type annotations,
|
||||
but `call_me` is missing the type annotation of `num`."""
|
||||
|
||||
[[exercises]]
|
||||
name = "functions3"
|
||||
path = "exercises/functions/functions3.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
This time, the function *declaration* is okay, but there's something wrong
|
||||
with the place where we're calling the function."""
|
||||
|
||||
[[exercises]]
|
||||
name = "functions4"
|
||||
path = "exercises/functions/functions4.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
The error message points to line 12 and says it expects a type after the
|
||||
`->`. This is where the function's return type should be-- take a look at
|
||||
the `is_even` function for an example!"""
|
||||
|
||||
[[exercises]]
|
||||
name = "functions5"
|
||||
path = "exercises/functions/functions5.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
This is a really common error that can be fixed by removing one character.
|
||||
It happens because Rust distinguishes between expressions and statements: expressions return
|
||||
a value based on its operand, and statements simply return a () type which behaves just like `void` in C/C++ language.
|
||||
We want to return a value of `i32` type from the `square` function, but it is returning a `()` type...
|
||||
They are not the same. There are two solutions:
|
||||
1. Add a `return` ahead of `num * num;`
|
||||
2. remove `;`, make it to be `num * num`
|
||||
"""
|
||||
|
||||
# TEST 1
|
||||
|
||||
@ -60,6 +114,7 @@ mode = "compile"
|
||||
name = "test1"
|
||||
path = "exercises/test1.rs"
|
||||
mode = "test"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# PRIMITIVE TYPES
|
||||
|
||||
@ -67,31 +122,64 @@ mode = "test"
|
||||
name = "primitive_types1"
|
||||
path = "exercises/primitive_types/primitive_types1.rs"
|
||||
mode = "compile"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
[[exercises]]
|
||||
name = "primitive_types2"
|
||||
path = "exercises/primitive_types/primitive_types2.rs"
|
||||
mode = "compile"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
[[exercises]]
|
||||
name = "primitive_types3"
|
||||
path = "exercises/primitive_types/primitive_types3.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
There's a shorthand to initialize Arrays with a certain size that does not
|
||||
require you to type in 100 items (but you certainly can if you want!).
|
||||
For example, you can do:
|
||||
let array = ["Are we there yet?"; 10];
|
||||
|
||||
Bonus: what are some other things you could have that would return true
|
||||
for `a.len() >= 100`?"""
|
||||
|
||||
[[exercises]]
|
||||
name = "primitive_types4"
|
||||
path = "exercises/primitive_types/primitive_types4.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
Take a look at the Understanding Ownership -> Slices -> Other Slices section of the book:
|
||||
https://doc.rust-lang.org/book/ch04-03-slices.html
|
||||
and use the starting and ending indices of the items in the Array
|
||||
that you want to end up in the slice.
|
||||
|
||||
If you're curious why the right hand of the `==` comparison does not
|
||||
have an ampersand for a reference since the left hand side is a
|
||||
reference, take a look at the Deref coercions section of the book:
|
||||
https://doc.rust-lang.org/book/ch15-02-deref.html
|
||||
"""
|
||||
|
||||
[[exercises]]
|
||||
name = "primitive_types5"
|
||||
path = "exercises/primitive_types/primitive_types5.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Take a look at the Data Types -> The Tuple Type section of the book:
|
||||
https://doc.rust-lang.org/book/ch03-02-data-types.html#the-tuple-type
|
||||
Particularly the part about destructuring (second to last example in the section).
|
||||
You'll need to make a pattern to bind `name` and `age` to the appropriate parts
|
||||
of the tuple. You can do it!!"""
|
||||
|
||||
[[exercises]]
|
||||
name = "primitive_types6"
|
||||
path = "exercises/primitive_types/primitive_types6.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
While you could use a destructuring `let` for the tuple here, try
|
||||
indexing into it instead, as explained in the last example of the
|
||||
Data Types -> The Tuple Type section of the book:
|
||||
https://doc.rust-lang.org/book/ch03-02-data-types.html#the-tuple-type
|
||||
Now you have another tool in your toolbox!"""
|
||||
|
||||
# STRUCTS
|
||||
|
||||
@ -99,11 +187,13 @@ mode = "compile"
|
||||
name = "structs1"
|
||||
path = "exercises/structs/structs1.rs"
|
||||
mode = "test"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
[[exercises]]
|
||||
name = "structs2"
|
||||
path = "exercises/structs/structs2.rs"
|
||||
mode = "test"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# STRINGS
|
||||
|
||||
@ -111,11 +201,22 @@ mode = "test"
|
||||
name = "strings1"
|
||||
path = "exercises/strings/strings1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
The `current_favorite_color` function is currently returning a string slice with the `'static`
|
||||
lifetime. We know this because the data of the string lives in our code itself -- it doesn't
|
||||
come from a file or user input or another program -- so it will live as long as our program
|
||||
lives. But it is still a string slice. There's one way to create a `String` by converting a
|
||||
string slice covered in the Strings chapter of the book, and another way that uses the `From`
|
||||
trait."""
|
||||
|
||||
[[exercises]]
|
||||
name = "strings2"
|
||||
path = "exercises/strings/strings2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Yes, it would be really easy to fix this by just changing the value bound to `word` to be a
|
||||
string slice instead of a `String`, wouldn't it?? There is a way to add one character to line
|
||||
6, though, that will coerce the `String` into a string slice."""
|
||||
|
||||
# TEST 2
|
||||
|
||||
@ -123,6 +224,7 @@ mode = "compile"
|
||||
name = "test2"
|
||||
path = "exercises/test2.rs"
|
||||
mode = "compile"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# ENUMS
|
||||
|
||||
@ -130,16 +232,22 @@ mode = "compile"
|
||||
name = "enums1"
|
||||
path = "exercises/enums/enums1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Hint: The declaration of the enumeration type has not been defined yet."""
|
||||
|
||||
[[exercises]]
|
||||
name = "enums2"
|
||||
path = "exercises/enums/enums2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Hint: you can create enumerations that have different variants with different types
|
||||
such as no data, anonymous structs, a single string, tuples, ...etc"""
|
||||
|
||||
[[exercises]]
|
||||
name = "enums3"
|
||||
path = "exercises/enums/enums3.rs"
|
||||
mode = "test"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# TESTS
|
||||
|
||||
@ -147,16 +255,31 @@ mode = "test"
|
||||
name = "tests1"
|
||||
path = "exercises/tests/tests1.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
You don't even need to write any code to test -- you can just test values and run that, even
|
||||
though you wouldn't do that in real life :) `assert!` is a macro that needs an argument.
|
||||
Depending on the value of the argument, `assert!` will do nothing (in which case the test will
|
||||
pass) or `assert!` will panic (in which case the test will fail). So try giving different values
|
||||
to `assert!` and see which ones compile, which ones pass, and which ones fail :)"""
|
||||
|
||||
[[exercises]]
|
||||
name = "tests2"
|
||||
path = "exercises/tests/tests2.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
Like the previous exercise, you don't need to write any code to get this test to compile and
|
||||
run. `assert_eq!` is a macro that takes two arguments and compares them. Try giving it two
|
||||
values that are equal! Try giving it two arguments that are different! Try giving it two values
|
||||
that are of different types! Try switching which argument comes first and which comes second!"""
|
||||
|
||||
[[exercises]]
|
||||
name = "tests3"
|
||||
path = "exercises/tests/tests3.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
You can call a function right where you're passing arguments to `assert!` -- so you could do
|
||||
something like `assert!(having_fun())`. If you want to check that you indeed get false, you
|
||||
can negate the result of what you're doing using `!`, like `assert!(!having_fun())`."""
|
||||
|
||||
# TEST 3
|
||||
|
||||
@ -164,6 +287,7 @@ mode = "test"
|
||||
name = "test3"
|
||||
path = "exercises/test3.rs"
|
||||
mode = "test"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# MODULES
|
||||
|
||||
@ -171,11 +295,21 @@ mode = "test"
|
||||
name = "modules1"
|
||||
path = "exercises/modules/modules1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Everything is private in Rust by default-- but there's a keyword we can use
|
||||
to make something public! The compiler error should point to the thing that
|
||||
needs to be public."""
|
||||
|
||||
[[exercises]]
|
||||
name = "modules2"
|
||||
path = "exercises/modules/modules2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
The delicious_snacks module is trying to present an external
|
||||
interface (the `fruit` and `veggie` constants) that is different than
|
||||
its internal structure (the `fruits` and `veggies` modules and
|
||||
associated constants). It's almost there except for one keyword missing for
|
||||
each constant."""
|
||||
|
||||
# MACROS
|
||||
|
||||
@ -183,28 +317,48 @@ mode = "compile"
|
||||
name = "macros1"
|
||||
path = "exercises/macros/macros1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
When you call a macro, you need to add something special compared to a
|
||||
regular function call. If you're stuck, take a look at what's inside
|
||||
`my_macro`."""
|
||||
|
||||
[[exercises]]
|
||||
name = "macros2"
|
||||
path = "exercises/macros/macros2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Macros don't quite play by the same rules as the rest of Rust, in terms of
|
||||
what's available where.
|
||||
|
||||
Unlike other things in Rust, the order of "where you define a macro" versus
|
||||
"where you use it" actually matters."""
|
||||
|
||||
[[exercises]]
|
||||
name = "macros3"
|
||||
path = "exercises/macros/macros3.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
In order to use a macro outside of its module, you need to do something
|
||||
special to the module to lift the macro out into its parent.
|
||||
|
||||
The same trick also works on "extern crate" statements for crates that have
|
||||
exported macros, if you've seen any of those around."""
|
||||
|
||||
[[exercises]]
|
||||
name = "macros4"
|
||||
path = "exercises/macros/macros4.rs"
|
||||
mode = "compile"
|
||||
|
||||
hint = """
|
||||
You only need to add a single character to make this compile.
|
||||
The way macros are written, it wants to see something between each
|
||||
"macro arm", so it can separate them."""
|
||||
# TEST 4
|
||||
|
||||
[[exercises]]
|
||||
name = "test4"
|
||||
path = "exercises/test4.rs"
|
||||
mode = "compile"
|
||||
hint = "No hints this time ;)"
|
||||
|
||||
# MOVE SEMANTICS
|
||||
|
||||
@ -212,21 +366,55 @@ mode = "compile"
|
||||
name = "move_semantics1"
|
||||
path = "exercises/move_semantics/move_semantics1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
So you've got the "cannot borrow immutable local variable `vec1` as mutable" error on line 11,
|
||||
right? The fix for this is going to be adding one keyword, and the addition is NOT on line 11
|
||||
where the error is."""
|
||||
|
||||
[[exercises]]
|
||||
name = "move_semantics2"
|
||||
path = "exercises/move_semantics/move_semantics2.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
So `vec0` is being *moved* into the function `fill_vec` when we call it on
|
||||
line 7, which means it gets dropped at the end of `fill_vec`, which means we
|
||||
can't use `vec0` again on line 10 (or anywhere else in `main` after the
|
||||
`fill_vec` call for that matter). We could fix this in a few ways, try them
|
||||
all!
|
||||
1. Make another, separate version of the data that's in `vec0` and pass that
|
||||
to `fill_vec` instead.
|
||||
2. Make `fill_vec` borrow its argument instead of taking ownership of it,
|
||||
and then copy the data within the function in order to return an owned
|
||||
`Vec<i32>`
|
||||
3. Make `fill_vec` *mutably* borrow its argument (which will need to be
|
||||
mutable), modify it directly, then not return anything. Then you can get rid
|
||||
of `vec1` entirely -- note that this will change what gets printed by the
|
||||
first `println!`"""
|
||||
|
||||
[[exercises]]
|
||||
name = "move_semantics3"
|
||||
path = "exercises/move_semantics/move_semantics3.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
The difference between this one and the previous ones is that the first line
|
||||
of `fn fill_vec` that had `let mut vec = vec;` is no longer there. You can,
|
||||
instead of adding that line back, add `mut` in one place that will change
|
||||
an existing binding to be a mutable binding instead of an immutable one :)"""
|
||||
|
||||
[[exercises]]
|
||||
name = "move_semantics4"
|
||||
path = "exercises/move_semantics/move_semantics4.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Stop reading whenever you feel like you have enough direction :) Or try
|
||||
doing one step and then fixing the compiler errors that result!
|
||||
So the end goal is to:
|
||||
- get rid of the first line in main that creates the new vector
|
||||
- so then `vec0` doesn't exist, so we can't pass it to `fill_vec`
|
||||
- we don't want to pass anything to `fill_vec`, so its signature should
|
||||
reflect that it does not take any arguments
|
||||
- since we're not creating a new vec in `main` anymore, we need to create
|
||||
a new vec in `fill_vec`, similarly to the way we did in `main`"""
|
||||
|
||||
# ERROR HANDLING
|
||||
|
||||
@ -234,21 +422,78 @@ mode = "compile"
|
||||
name = "errors1"
|
||||
path = "exercises/error_handling/errors1.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
`Err` is one of the variants of `Result`, so what the 2nd test is saying
|
||||
is that `generate_nametag_text` should return a `Result` instead of an
|
||||
`Option`.
|
||||
|
||||
To make this change, you'll need to:
|
||||
- update the return type in the function signature to be a Result<String, String> that
|
||||
could be the variants `Ok(String)` and `Err(String)`
|
||||
- change the body of the function to return `Ok(stuff)` where it currently
|
||||
returns `Some(stuff)`
|
||||
- change the body of the function to return `Err(error message)` where it
|
||||
currently returns `None`
|
||||
- change the first test to expect `Ok(stuff)` where it currently expects
|
||||
`Some(stuff)`."""
|
||||
|
||||
[[exercises]]
|
||||
name = "errors2"
|
||||
path = "exercises/error_handling/errors2.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
One way to handle this is using a `match` statement on
|
||||
`item_quantity.parse::<i32>()` where the cases are `Ok(something)` and
|
||||
`Err(something)`. This pattern is very common in Rust, though, so there's
|
||||
a `?` operator that does pretty much what you would make that match statement
|
||||
do for you! Take a look at this section of the Error Handling chapter:
|
||||
https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
|
||||
and give it a try!"""
|
||||
|
||||
[[exercises]]
|
||||
name = "errors3"
|
||||
path = "exercises/error_handling/errors3.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
If other functions can return a `Result`, why shouldn't `main`?"""
|
||||
|
||||
[[exercises]]
|
||||
name = "errors4"
|
||||
path = "exercises/error_handling/errorsn.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
First hint: To figure out what type should go where the ??? is, take a look
|
||||
at the test helper function `test_with_str`, since it returns whatever
|
||||
`read_and_validate` returns and`test_with_str` has its signature fully
|
||||
specified.
|
||||
|
||||
|
||||
Next hint: There are three places in `read_and_validate` that we call a
|
||||
function that returns a `Result` (that is, the functions might fail).
|
||||
Apply the `?` operator on those calls so that we return immediately from
|
||||
`read_and_validate` if those function calls fail.
|
||||
|
||||
|
||||
Another hint: under the hood, the `?` operator calls `From::from`
|
||||
on the error value to convert it to a boxed trait object, a Box<dyn error::Error>,
|
||||
which is polymorphic-- that means that lots of different kinds of errors
|
||||
can be returned from the same function because all errors act the same
|
||||
since they all implement the `error::Error` trait.
|
||||
Check out this section of the book:
|
||||
https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
|
||||
|
||||
|
||||
Another another hint: Note that because the `?` operator returns
|
||||
the *unwrapped* value in the `Ok` case, if we want to return a `Result` from
|
||||
`read_and_validate` for *its* success case, we'll have to rewrap a value
|
||||
that we got from the return value of a `?`ed call in an `Ok`-- this will
|
||||
look like `Ok(something)`.
|
||||
|
||||
|
||||
Another another another hint: `Result`s must be "used", that is, you'll
|
||||
get a warning if you don't handle a `Result` that you get in your
|
||||
function. Read more about that in the `std::result` module docs:
|
||||
https://doc.rust-lang.org/std/result/#results-must-be-used"""
|
||||
|
||||
# OPTIONS / RESULTS
|
||||
|
||||
@ -256,11 +501,21 @@ mode = "test"
|
||||
name = "option1"
|
||||
path = "exercises/error_handling/option1.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
Try using a `match` statement where the arms are `Some(thing)` and `None`.
|
||||
Or set a default value to print out if you get `None` by using the
|
||||
function `unwrap_or`.
|
||||
Or use an `if let` statement on the result of `pop()` to both destructure
|
||||
a `Some` value and only print out something if we have a value!"""
|
||||
|
||||
[[exercises]]
|
||||
name = "option2"
|
||||
path = "exercises/error_handling/result1.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
`PositiveNonzeroInteger::new` is always creating a new instance and returning an `Ok` result.
|
||||
It should be doing some checking, returning an `Err` result if those checks fail, and only
|
||||
returning an `Ok` result if those checks determine that everything is... okay :)"""
|
||||
|
||||
# STANDARD LIBRARY TYPES
|
||||
|
||||
@ -268,21 +523,56 @@ mode = "test"
|
||||
name = "arc1"
|
||||
path = "exercises/standard_library_types/arc1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
Make `shared_numbers` be an `Arc` from the numbers vector. Then, in order
|
||||
to avoid creating a copy of `numbers`, you'll need to create `child_numbers`
|
||||
inside the loop but still in the main thread.
|
||||
|
||||
`child_numbers` should be a clone of the Arc of the numbers instead of a
|
||||
thread-local copy of the numbers."""
|
||||
|
||||
[[exercises]]
|
||||
name = "iterators2"
|
||||
path = "exercises/standard_library_types/iterators2.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
Step 1
|
||||
You need to call something on `first` before it can be collected
|
||||
Currently its type is `char`. Have a look at the methods that are available on that type:
|
||||
https://doc.rust-lang.org/std/primitive.char.html
|
||||
|
||||
|
||||
Step 2
|
||||
First you'll need to turn the Vec into an iterator
|
||||
Then you'll need to apply your function unto each item in the vector
|
||||
P.s. Don't forget to collect() at the end!
|
||||
|
||||
|
||||
Step 3.
|
||||
This is very similar to the previous test. The only real change is that you will need to
|
||||
alter the type that collect is coerced into. For a bonus you could try doing this with a
|
||||
turbofish"""
|
||||
|
||||
[[exercises]]
|
||||
name = "iterators3"
|
||||
path = "exercises/standard_library_types/iterators3.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
Minor hint: In each of the two cases in the match in main, you can create x with either
|
||||
a 'turbofish' or by hinting the type of x to the compiler. You may try both.
|
||||
|
||||
Major hint: Have a look at the Iter trait and at the explanation of its collect function.
|
||||
Especially the part about Result is interesting."""
|
||||
|
||||
[[exercises]]
|
||||
name = "iterators4"
|
||||
path = "exercises/standard_library_types/iterators4.rs"
|
||||
mode = "test"
|
||||
hint = """
|
||||
In an imperative language you might write a for loop to iterate through
|
||||
multiply the values into a mutable variable. Or you might write code more
|
||||
functionally with recursion and a match clause. But you can also use ranges
|
||||
and iterators to solve this in rust."""
|
||||
|
||||
# THREADS
|
||||
|
||||
@ -290,3 +580,35 @@ mode = "test"
|
||||
name = "threads1"
|
||||
path = "exercises/threads/threads1.rs"
|
||||
mode = "compile"
|
||||
hint = """
|
||||
`Arc` is an Atomic Reference Counted pointer that allows safe, shared access
|
||||
to **immutable** data. But we want to *change* the number of `jobs_completed`
|
||||
so we'll need to also use another type that will only allow one thread to
|
||||
mutate the data at a time. Take a look at this section of the book:
|
||||
https://doc.rust-lang.org/book/ch16-03-shared-state.html#atomic-reference-counting-with-arct
|
||||
and keep reading if you'd like more hints :)
|
||||
|
||||
|
||||
Do you now have an `Arc` `Mutex` `JobStatus` at the beginning of main? Like:
|
||||
`let status = Arc::new(Mutex::new(JobStatus { jobs_completed: 0 }));`
|
||||
Similar to the code in the example in the book that happens after the text
|
||||
that says "We can use Arc<T> to fix this.". If not, give that a try! If you
|
||||
do and would like more hints, keep reading!!
|
||||
|
||||
|
||||
Make sure neither of your threads are holding onto the lock of the mutex
|
||||
while they are sleeping, since this will prevent the other thread from
|
||||
being allowed to get the lock. Locks are automatically released when
|
||||
they go out of scope.
|
||||
|
||||
Ok, so, real talk, this was actually tricky for *me* to do too. And
|
||||
I could see a lot of different problems you might run into, so at this
|
||||
point I'm not sure which one you've hit :)
|
||||
|
||||
Please open an issue if you're still running into a problem that
|
||||
these hints are not helping you with, or if you've looked at the sample
|
||||
answers and don't understand why they work and yours doesn't.
|
||||
|
||||
If you've learned from the sample solutions, I encourage you to come
|
||||
back to this exercise and try it again in a few days to reinforce
|
||||
what you've learned :)"""
|
||||
|
@ -27,6 +27,7 @@ pub struct Exercise {
|
||||
pub name: String,
|
||||
pub path: PathBuf,
|
||||
pub mode: Mode,
|
||||
pub hint: String,
|
||||
}
|
||||
|
||||
impl Exercise {
|
||||
@ -74,6 +75,7 @@ mod test {
|
||||
name: String::from("example"),
|
||||
path: PathBuf::from("example.rs"),
|
||||
mode: Mode::Test,
|
||||
hint: String::from(""),
|
||||
};
|
||||
exercise.clean();
|
||||
assert!(!Path::new(&temp_file()).exists());
|
||||
|
20
src/main.rs
20
src/main.rs
@ -27,6 +27,12 @@ fn main() {
|
||||
.about("Runs/Tests a single exercise")
|
||||
.arg(Arg::with_name("name").required(true).index(1)),
|
||||
)
|
||||
.subcommand(
|
||||
SubCommand::with_name("hint")
|
||||
.alias("h")
|
||||
.about("Returns a hint for the current exercise")
|
||||
.arg(Arg::with_name("name").required(true).index(1)),
|
||||
)
|
||||
.get_matches();
|
||||
|
||||
if None == matches.subcommand_name() {
|
||||
@ -71,6 +77,20 @@ fn main() {
|
||||
run(&exercise).unwrap_or_else(|_| std::process::exit(1));
|
||||
}
|
||||
|
||||
if let Some(ref matches) = matches.subcommand_matches("hint") {
|
||||
let name = matches.value_of("name").unwrap_or_else(|| {
|
||||
println!("Please supply an exercise name!");
|
||||
std::process::exit(1);
|
||||
});
|
||||
|
||||
let exercise = exercises.iter().find(|e| name == e.name).unwrap_or_else(|| {
|
||||
println!("No exercise found for your given name!");
|
||||
std::process::exit(1)
|
||||
});
|
||||
|
||||
println!("{}", exercise.hint);
|
||||
}
|
||||
|
||||
if matches.subcommand_matches("verify").is_some() {
|
||||
verify(&exercises).unwrap_or_else(|_| std::process::exit(1));
|
||||
}
|
||||
|
@ -2,8 +2,10 @@
|
||||
name = "compFailure"
|
||||
path = "compFailure.rs"
|
||||
mode = "compile"
|
||||
hint = """"""
|
||||
|
||||
[[exercises]]
|
||||
name = "testFailure"
|
||||
path = "testFailure.rs"
|
||||
mode = "test"
|
||||
hint = """"""
|
||||
|
@ -2,8 +2,10 @@
|
||||
name = "compSuccess"
|
||||
path = "compSuccess.rs"
|
||||
mode = "compile"
|
||||
hint = """"""
|
||||
|
||||
[[exercises]]
|
||||
name = "testSuccess"
|
||||
path = "testSuccess.rs"
|
||||
mode = "test"
|
||||
hint = """"""
|
||||
|
Loading…
Reference in New Issue
Block a user