Rust facts & stats

Question 1

What is Rust's official build tool and package manager called?

Accepted Answer

Cargo. Cargo builds Rust projects, runs tests and downloads dependencies.

Question 2

Rust's unofficial crab mascot is named what?

Accepted Answer

Ferris. Ferris the crab is the community mascot, and Rust fans call themselves Rustaceans.

Question 3

By default, variables declared with let in Rust are what?

Accepted Answer

Immutable. Rust variables cannot be changed unless declared with let mut.

Question 4

Instead of null values, Rust usually represents a value that might be missing with which type?

Accepted Answer

Option. Option has two variants: Some(value) or None.

Question 5

How does Rust achieve memory safety without a garbage collector?

Accepted Answer

Ownership and borrowing rules checked at compile time. Rust's compiler tracks which part of the program owns each value and frees memory when the owner goes out of scope.

Question 6

Which Rust type is commonly returned by operations that can fail?

Accepted Answer

Result. Result has Ok(value) for success and Err(error) for failure.

Question 7

Which Rust keyword marks code the compiler cannot fully check for memory safety, such as dereferencing raw pointers?

Accepted Answer

unsafe. Inside an unsafe block the programmer takes responsibility for upholding Rust's safety rules.

Rust facts & stats

The basics