Step 1.9: Phantom types

[ziimakc]

Resolves Step 1.9

Task

Implement a Fact<T> type which returns some random fact about T type that Fact<T> is implemented for.

let f: Fact<Vec<T>> = Fact::new();
println!("Fact about Vec: {}", f.fact());
println!("Fact about Vec: {}", f.fact());

Fact about Vec: Vec is heap-allocated.
Fact about Vec: Vec may re-allocate on growing.

Solution

Implement Fact<T> using PhantomData.