From a96bbcd9675933b19454d627ab6291d4739f0e53 Mon Sep 17 00:00:00 2001 From: luhem7 Date: Sat, 3 Jun 2023 10:20:29 -0400 Subject: [PATCH] fix(threads, smart pointers): Swap order of threads and smart pointers exercises closes #1541 --- info.toml | 122 +++++++++++++++++++++++++++--------------------------- 1 file changed, 61 insertions(+), 61 deletions(-) diff --git a/info.toml b/info.toml index 2add5f0ccf..3abb2f8c55 100644 --- a/info.toml +++ b/info.toml @@ -905,67 +905,6 @@ The fold method can be useful in the count_collection_iterator function. For a further challenge, consult the documentation for Iterator to find a different method that could make your code more compact than using fold.""" -# THREADS - -[[exercises]] -name = "threads1" -path = "exercises/threads/threads1.rs" -mode = "compile" -hint = """ -`JoinHandle` is a struct that is returned from a spawned thread: -https://doc.rust-lang.org/std/thread/fn.spawn.html - -A challenge with multi-threaded applications is that the main thread can -finish before the spawned threads are completed. -https://doc.rust-lang.org/book/ch16-01-threads.html#waiting-for-all-threads-to-finish-using-join-handles - -Use the JoinHandles to wait for each thread to finish and collect their results. -https://doc.rust-lang.org/std/thread/struct.JoinHandle.html -""" - -[[exercises]] -name = "threads2" -path = "exercises/threads/threads2.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 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. - -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 :)""" - -[[exercises]] -name = "threads3" -path = "exercises/threads/threads3.rs" -mode = "compile" -hint = """ -An alternate way to handle concurrency between threads is to use -a mpsc (multiple producer, single consumer) channel to communicate. -With both a sending end and a receiving end, it's possible to -send values in one thread and receive them in another. -Multiple producers are possible by using clone() to create a duplicate -of the original sending end. -See https://doc.rust-lang.org/book/ch16-02-message-passing.html for more info. -""" - # SMART POINTERS [[exercises]] @@ -1028,6 +967,67 @@ Check out https://doc.rust-lang.org/std/borrow/enum.Cow.html for documentation on the `Cow` type. """ +# THREADS + +[[exercises]] +name = "threads1" +path = "exercises/threads/threads1.rs" +mode = "compile" +hint = """ +`JoinHandle` is a struct that is returned from a spawned thread: +https://doc.rust-lang.org/std/thread/fn.spawn.html + +A challenge with multi-threaded applications is that the main thread can +finish before the spawned threads are completed. +https://doc.rust-lang.org/book/ch16-01-threads.html#waiting-for-all-threads-to-finish-using-join-handles + +Use the JoinHandles to wait for each thread to finish and collect their results. +https://doc.rust-lang.org/std/thread/struct.JoinHandle.html +""" + +[[exercises]] +name = "threads2" +path = "exercises/threads/threads2.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 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. + +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 :)""" + +[[exercises]] +name = "threads3" +path = "exercises/threads/threads3.rs" +mode = "compile" +hint = """ +An alternate way to handle concurrency between threads is to use +a mpsc (multiple producer, single consumer) channel to communicate. +With both a sending end and a receiving end, it's possible to +send values in one thread and receive them in another. +Multiple producers are possible by using clone() to create a duplicate +of the original sending end. +See https://doc.rust-lang.org/book/ch16-02-message-passing.html for more info. +""" + # MACROS [[exercises]]