Generic constraints with where clause in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a generic function with a constraint using the where clause.

Kotlin

fun <T> checkValue(value: T) where T : [1] {
    println(value)
}

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

ANumber

BString

CAny

DList

Attempts:

3 left

💡 Hint

Common Mistakes

Using a class like String which is not a numeric type.

Not using the where clause properly.

Using Any which does not constrain the type.

The generic type T is constrained to Number using the where clause, so only types that inherit from Number are allowed.

2fill in blank

medium

Complete the code to declare a generic function with two constraints using the where clause.

Kotlin

fun <T> process(item: T) where T : Comparable<T>, T : [1] {
    println(item)
}

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

ACharSequence

BNumber

CList

DAny

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-numeric type like CharSequence.

Not including both constraints properly.

Using Any which does not constrain the type.

The generic type T is constrained to both Comparable<T> and Number, so it must be a numeric type that can be compared.

3fill in blank

hard

Fix the error in the generic function declaration by completing the where clause correctly.

Kotlin

fun <T> compareValues(a: T, b: T) where T : [1], T : Comparable<T> {
    println(if (a > b) a else b)
}

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

AAny

BString

CNumber

DList

Attempts:

3 left

💡 Hint

Common Mistakes

Using Any which does not guarantee comparability.

Using String which is not numeric.

Omitting the where clause.

The function requires T to be a Number and also implement Comparable<T> to use the comparison operator.

4fill in blank

hard

Fill both blanks to declare a generic function with constraints that T must be a Number and implement Comparable.

Kotlin

fun <T> maxValue(a: T, b: T) where T : [1], T : [2] {
    println(if (a > b) a else b)
}

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

ANumber

BCharSequence

CComparable<T>

DList

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the order of constraints incorrectly.

Using non-numeric or non-comparable types.

Omitting one of the constraints.

The generic type T must be a Number and implement Comparable<T> to allow comparison.

5fill in blank

hard

Fill all three blanks to declare a generic function with constraints that T must be a Number, implement Comparable, and also implement CharSequence.

Kotlin

fun <T> complexCheck(item: T) where T : [1], T : [2], T : [3] {
    println(item)
}

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

ANumber

BComparable<T>

CCharSequence

DList

Attempts:

3 left

💡 Hint

Common Mistakes

Using incompatible types together.

Omitting one or more constraints.

Mixing up the order of constraints.

The generic type T must be a Number, implement Comparable<T>, and also implement CharSequence to satisfy all constraints.