rust!

exercises/14_generics/README.md

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+# Generics
+
+Generics is the topic of generalizing types and functionalities to broader cases.
+This is extremely useful for reducing code duplication in many ways, but can call for some rather involved syntax.
+Namely, being generic requires taking great care to specify over which types a generic type is actually considered valid.
+The simplest and most common use of generics is for type parameters.
+
+## Further information
+
+- [Generic Data Types](https://doc.rust-lang.org/book/ch10-01-syntax.html)
+- [Bounds](https://doc.rust-lang.org/rust-by-example/generics/bounds.html)

exercises/14_generics/generics1.rs

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+// `Vec<T>` is generic over the type `T`. In most cases, the compiler is able to
+// infer `T`, for example after pushing a value with a concrete type to the vector.
+// But in this exercise, the compiler needs some help through a type annotation.
+
+fn main() {
+    // TODO: Fix the compiler error by annotating the type of the vector
+    // `Vec<T>`. Choose `T` as some integer type that can be created from
+    // `u8` and `i8`.
+    let mut numbers = Vec::new();
+
+    // Don't change the lines below.
+    let n1: u8 = 42;
+    numbers.push(n1.into());
+    let n2: i8 = -1;
+    numbers.push(n2.into());
+
+    println!("{numbers:?}");
+}

exercises/14_generics/generics2.rs

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+// This powerful wrapper provides the ability to store a positive integer value.
+// TODO: Rewrite it using a generic so that it supports wrapping ANY type.
+struct Wrapper {
+    value: u32,
+}
+
+// TODO: Adapt the struct's implementation to be generic over the wrapped value.
+impl Wrapper {
+    fn new(value: u32) -> Self {
+        Wrapper { value }
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn store_u32_in_wrapper() {
+        assert_eq!(Wrapper::new(42).value, 42);
+    }
+
+    #[test]
+    fn store_str_in_wrapper() {
+        assert_eq!(Wrapper::new("Foo").value, "Foo");
+    }
+}