1 files changed, 54 insertions, 0 deletions
diff --git a/old_curriculum/move_semantics/move_semantics2.rs b/old_curriculum/move_semantics/move_semantics2.rs
new file mode 100644
index 0000000..bc42d8e
--- /dev/null
+++ b/old_curriculum/move_semantics/move_semantics2.rs
@@ -0,0 +1,54 @@
+// move_semantics2.rs
+// Make me compile without changing line 10! Scroll down for hints :)
+
+pub fn main() {
+    let vec0 = Vec::new();
+
+    let mut vec1 = fill_vec(vec0);
+
+    // Do not change the following line!
+    println!("{} has length {} content `{:?}`", "vec0", vec0.len(), vec0);
+
+    vec1.push(88);
+
+    println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
+
+}
+
+fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+    let mut vec = vec;
+
+    vec.push(22);
+    vec.push(44);
+    vec.push(66);
+
+    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!`