arc and moo cow

exercises/19_smart_pointers/arc1.rs

@@ -21,19 +21,17 @@
 //
 // Execute `rustlings hint arc1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 #![forbid(unused_imports)] // Do not change this, (or the next) line.
 use std::sync::Arc;
 use std::thread;
 
 fn main() {
     let numbers: Vec<_> = (0..100u32).collect();
-    let shared_numbers = // TODO
+    let shared_numbers = Arc::new(numbers); // TODO
     let mut joinhandles = Vec::new();
 
     for offset in 0..8 {
-        let child_numbers = // TODO
+        let child_numbers = Arc::clone(&shared_numbers); // TODO
         joinhandles.push(thread::spawn(move || {
             let sum: u32 = child_numbers.iter().filter(|&&n| n % 8 == offset).sum();
             println!("Sum of offset {} is {}", offset, sum);

exercises/19_smart_pointers/cow1.rs

@@ -12,8 +12,6 @@
 //
 // Execute `rustlings hint cow1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 use std::borrow::Cow;
 
 fn abs_all<'a, 'b>(input: &'a mut Cow<'b, [i32]>) -> &'a mut Cow<'b, [i32]> {
@@ -49,6 +47,8 @@ mod tests {
         let mut input = Cow::from(&slice[..]);
         match abs_all(&mut input) {
             // TODO
+            Cow::Borrowed(_) => Ok(()),
+            _ => Err("Expected a reference I suppose?"),
         }
     }
 
@@ -61,6 +61,8 @@ mod tests {
         let mut input = Cow::from(slice);
         match abs_all(&mut input) {
             // TODO
+            Cow::Owned(_) => Ok(()),
+            _ => Err("Expected owned value"),
         }
     }
 
@@ -73,6 +75,8 @@ mod tests {
         let mut input = Cow::from(slice);
         match abs_all(&mut input) {
             // TODO
+            Cow::Owned(_) => Ok(()),
+            _ => Err("Expected owned value"),
         }
     }
 }