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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 rather involving 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/stable/book/ch10-01-syntax.html)
+- [Bounds](https://doc.rust-lang.org/rust-by-example/generics/bounds.html)

generics/generics1.rs

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+// generics1.rs
+//
+// This shopping list program isn't compiling! Use your knowledge of generics to
+// fix it.
+//
+// Execute `rustlings hint generics1` or use the `hint` watch subcommand for a
+// hint.
+
+// I AM DONE
+
+fn main() {
+    let mut shopping_list: Vec<&str> = Vec::new();
+    shopping_list.push("milk");
+}

generics/generics2.rs

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+// generics2.rs
+//
+// This powerful wrapper provides the ability to store a positive integer value.
+// Rewrite it using generics so that it supports wrapping ANY type.
+//
+// Execute `rustlings hint generics2` or use the `hint` watch subcommand for a
+// hint.
+
+// I AM DONE
+
+struct Wrapper<T> {
+    value: T,
+}
+
+impl<T> Wrapper<T> {
+    pub fn new(value: T) -> Self {
+        Wrapper { value }
+    }
+}
+
+#[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");
+    }
+}