Why generics are needed in Rust - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a function that returns the first element of a slice.

Rust

fn first_element(slice: &[[1]]) -> &[1] {
    &slice[0]
}

Drag options to blanks, or click blank then click option'

Ai32

BT

CString

Dbool

Attempts:

3 left

💡 Hint

Common Mistakes

Using a specific type like i32 limits the function to only that type.

Forgetting to use a generic type causes the function to be less flexible.

Using T as a generic type allows the function to work with any type of slice.

2fill in blank

medium

Complete the code to declare a generic struct named Point.

Rust

struct Point<[1]> {
    x: T,
    y: T,
}

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AV

BPoint

CU

DT

Attempts:

3 left

💡 Hint

Common Mistakes

Using a name that does not match the field types.

Not declaring the generic type in angle brackets.

The generic type T allows the struct to hold any type for its fields.

3fill in blank

hard

Fix the error in the function signature to make it generic.

Rust

fn print_value(value: [1]) {
    println!("{}", value);
}

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AT

Bi32

C&str

DString

Attempts:

3 left

💡 Hint

Common Mistakes

Using a concrete type instead of a generic type.

Not declaring the generic type parameter.

Using T as a generic type requires declaring it in the function signature with <T>.

4fill in blank

hard

Fill both blanks to define a generic function that returns the larger of two values.

Rust

fn max_value<[1]: PartialOrd>(a: [1], b: [1]) -> [1] {
    if a > b { a } else { b }
}

Drag options to blanks, or click blank then click option'

AT

BU

CV

DW

Attempts:

3 left

💡 Hint

Common Mistakes

Using different generic type names inconsistently.

Not adding the trait bound : PartialOrd.

The generic type T is used consistently and constrained by PartialOrd to allow comparison.

5fill in blank

hard

Fill all three blanks to implement a generic struct with two different types.

Rust

struct Pair<[1], [2]> {
    first: [1],
    second: [2],
}

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AT

BU

CV

DW

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same generic type for both fields when different types are needed.

Not declaring both generic types in the struct definition.

The struct uses two generic types T and U for its fields.