Merge pull request #489 from mukundbhudia/iterators1

This commit is contained in:
fmoko 2020-09-18 15:23:28 +02:00 committed by GitHub
commit 0f16463794
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 45 additions and 2 deletions

View file

@ -3,5 +3,3 @@ For the Box exercise check out the chapter [Using Box to Point to Data on the He
For the Arc exercise check out the chapter [Shared-State Concurrency](https://doc.rust-lang.org/book/ch16-03-shared-state.html) of the Rust Book.
For the Iterator exercise check out the chapters [Iterator](https://doc.rust-lang.org/book/ch13-02-iterators.html) of the Rust Book and the [Iterator documentation](https://doc.rust-lang.org/stable/std/iter/).
Do not adjust your monitors-- iterators1.rs is indeed missing. Iterators is a challenging topic, so we're leaving space for a simpler exercise!

View file

@ -0,0 +1,24 @@
// iterators1.rs
//
// Make me compile by filling in the `???`s
//
// When performing operations on elements within a collection, iterators are essential.
// This module helps you get familiar with the structure of using an iterator and
// how to go through elements within an iterable collection.
//
// Execute `rustlings hint iterators1` for hints :D
// I AM NOT DONE
fn main () {
let my_fav_fruits = vec!["banana", "custard apple", "avocado", "peach", "raspberry"];
let mut my_iterable_fav_fruits = ???; // TODO: Step 1
assert_eq!(my_iterable_fav_fruits.next(), Some(&"banana"));
assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 2
assert_eq!(my_iterable_fav_fruits.next(), Some(&"avocado"));
assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 2.1
assert_eq!(my_iterable_fav_fruits.next(), Some(&"raspberry"));
assert_eq!(my_iterable_fav_fruits.next(), ???); // TODO: Step 3
}

View file

@ -644,6 +644,27 @@ 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 = "iterators1"
path = "exercises/standard_library_types/iterators1.rs"
mode = "compile"
hint = """
Step 1:
We need to apply something to the collection `my_fav_fruits` before we start to go through
it. What could that be? Take a look at the struct definition for a vector for inspiration:
https://doc.rust-lang.org/std/vec/struct.Vec.html.
Step 2 & step 2.1:
Very similar to the lines above and below. You've got this!
Step 3:
An iterator goes through all elements in a collection, but what if we've run out of
elements? What should we expect here? If you're stuck, take a look at
https://doc.rust-lang.org/std/iter/trait.Iterator.html for some ideas.
"""
[[exercises]]
name = "iterators2"
path = "exercises/standard_library_types/iterators2.rs"