Functional Data Structures

1. What is a good library to serialize and deserialize data?

We recommend serde.

2. What do the hashtag derive lines in front of the struct declarations in physics.rs do?

These are macros that will automatically derive trait implementations for these data structures.

3. Which comes first in parameterized declarations—lifetimes or traits?

Lifetime parameters must come before trait parameters in parameter declarations.

4. In a trait implementation, what is the difference between parameters on the impl, trait, or type?

The impl<A,...> syntax defines what symbols will be parameterized. The Trait<A,...> syntax defines what trait is being implemented. The Type<A,...> syntax defines what type the trait is being implemented for.

5. What is the difference between a trait and a data class?

The term data class is not a Rust term. Think of a data class as if it were a trait but without fewer limitations than what Rust might impose.

6. How should you declare that a package has multiple binaries?

In Cargo.toml, list all of the binaries and their entry points:

[[bin]]
name = "binary1"
path = "binary1.rs"

[[bin]]
name = "binary2"
path = "binary2.rs"

7. How do you declare a structure field as private?

Do not declare it as public. Fields are private by default.