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Diffstat (limited to 'rustlings/exercises/14_generics')
| -rw-r--r-- | rustlings/exercises/14_generics/README.md | 11 | ||||
| -rw-r--r-- | rustlings/exercises/14_generics/generics1.rs | 18 | ||||
| -rw-r--r-- | rustlings/exercises/14_generics/generics2.rs | 31 |
3 files changed, 60 insertions, 0 deletions
diff --git a/rustlings/exercises/14_generics/README.md b/rustlings/exercises/14_generics/README.md new file mode 100644 index 0000000..0c8c8cb --- /dev/null +++ b/rustlings/exercises/14_generics/README.md @@ -0,0 +1,11 @@ +# 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) diff --git a/rustlings/exercises/14_generics/generics1.rs b/rustlings/exercises/14_generics/generics1.rs new file mode 100644 index 0000000..87ed990 --- /dev/null +++ b/rustlings/exercises/14_generics/generics1.rs @@ -0,0 +1,18 @@ +// `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:?}"); +} diff --git a/rustlings/exercises/14_generics/generics2.rs b/rustlings/exercises/14_generics/generics2.rs new file mode 100644 index 0000000..8908725 --- /dev/null +++ b/rustlings/exercises/14_generics/generics2.rs @@ -0,0 +1,31 @@ +// 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"); + } +} |