100-exercises-to-learn-rust/book/src/04_traits/00_intro.md

Traits

In the previous chapter we covered the basics of Rust’s type and ownership system.
It’s time to dig deeper: we’ll explore traits, Rust’s take on interfaces.

Once you learn about traits, you’ll start seeing their fingerprints all over the place.
In fact, you’ve already seen traits in action throughout the previous chapter, e.g. .into() invocations as well as operators like == and +.

On top of traits as a concept, we’ll also cover some of the key traits that are defined in Rust’s standard library:

• Operator traits (e.g. Add, Sub, PartialEq, etc.)
• From and Into, for infallible conversions
• Clone and Copy, for copying values
• Deref and deref coercion
• Sized, to mark types with a known size
• Drop, for custom cleanup logic

Since we’ll be talking about conversions, we’ll seize the opportunity to plug some of the “knowledge gaps” from the previous chapter—e.g. what is "A title", exactly? Time to learn more about slices too!