get functions

src/SUMMARY.md

@@ -11,6 +11,7 @@
   - [BoolStream](./exercises/bool_stream.md)
   - [RcChars](./exercises/rcchars.md)
   - [Async Fn](./exercises/async_fn.md)
+  - [Get Functions](./exercises/get_functions.md)
 - [Chapter 2](./chapter_2.md)
   - [AnyStr](./exercises/anystr.md)
   - [Mode](./exercises/mode.md)

src/exercises/get_functions.md

@@ -0,0 +1,44 @@
+# Get `Functions`
+
+Edit the body of `get_functions` to make this compile and pass tests:
+
+```rust
+struct Functions {
+    five: fn() -> i32,
+    increment: fn(i32) -> i32,
+}
+
+fn get_functions() -> &'static Functions {
+# /*
+    let five = || 5;
+    let increment = |n| n + 1;
+    let functions = Functions { five, increment };
+    &functions
+# */
+# &Functions { five: || 5, increment: |n| n + 1 }
+}
+
+assert_eq!((get_functions().five)(), 5);
+assert_eq!((get_functions().increment)(4), 5);
+```
+
+Try solving it in the playground:
+
+```rust,editable,compile_fail
+struct Functions {
+    five: fn() -> i32,
+    increment: fn(i32) -> i32,
+}
+
+fn get_functions() -> &'static Functions {
+    let five = || 5;
+    let increment = |n| n + 1;
+    let functions = Functions { five, increment };
+    &functions
+}
+
+fn main() {
+    assert_eq!((get_functions().five)(), 5);
+    assert_eq!((get_functions().increment)(4), 5);
+}
+```