Result type for functional error handling in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a successful Result with value 42.

Kotlin

val result: Result<Int> = Result.[1](42)

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Aof

BrunCatching

Csuccess

Dfailure

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'failure' instead of 'success' creates an error Result.

Using 'runCatching' requires a lambda, not a direct value.

Use Result.success(value) to create a successful Result wrapping the value.

2fill in blank

medium

Complete the code to create a failed Result with an exception.

Kotlin

val errorResult: Result<Int> = Result.[1](IllegalArgumentException("Invalid input"))

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Aof

BrunCatching

Csuccess

Dfailure

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'success' instead of 'failure' creates a success Result.

Using 'runCatching' requires a lambda, not an exception directly.

Use Result.failure(exception) to create a failed Result wrapping the exception.

3fill in blank

hard

Fix the error in the code to catch exceptions and return a Result.

Kotlin

val result = Result.[1] { 10 / 0 }

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ArunCatching

Bsuccess

Cfailure

Dof

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'success' or 'failure' directly does not execute the lambda.

Using 'of' is not a standard Result function.

runCatching runs the lambda and catches exceptions, returning a Result.

4fill in blank

hard

Fill both blanks to create a map operation on a Result.

Kotlin

val mapped = result.[1] { it [2] 2 }

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Amap

B*

C+

Dfold

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'fold' instead of 'map' changes the Result type.

Using '+' instead of '*' changes the operation.

Use map to transform the success value, and * to multiply by 2.

5fill in blank

hard

Fill all three blanks to handle success and failure with fold.

Kotlin

val message = result.[1](
  onSuccess = { "Success: " + it.toString() },
  onFailure = { [2] -> "Error: " + [3].message }
)

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Afold

Be

Dmap

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'map' instead of 'fold' only handles success.

Using different names for the failure parameter and usage causes errors.

fold handles both success and failure. The failure lambda parameter is named e to access the exception.