Multiline strings with trimIndent in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a multiline string using triple quotes.

Kotlin

val text = [1]
    Hello, Kotlin!
    Welcome to multiline strings.
"""

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

A"

B"""

C'

D`

Attempts:

3 left

💡 Hint

Common Mistakes

Using single quotes instead of triple quotes.

Using backticks which are for identifiers, not strings.

Triple quotes """ are used in Kotlin to create multiline strings.

2fill in blank

medium

Complete the code to remove leading indentation from the multiline string.

Kotlin

val text = """
    Kotlin is fun.
    Let's learn together.
""".[1]()

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

AtrimIndent

BtrimStart

CtrimMargin

DtrimEnd

Attempts:

3 left

💡 Hint

Common Mistakes

Using trimMargin() which requires a margin prefix.

Using trimStart() or trimEnd() which only trim spaces at start or end of the whole string.

trimIndent() removes the common minimal indentation from every line in the string.

3fill in blank

hard

Fix the error in the code to correctly trim indentation from the multiline string.

Kotlin

val message = """
        Welcome to Kotlin!
        Enjoy coding.
    """.[1]()

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

AtrimMargin

BstripIndent

Ctrim

DtrimIndent

Attempts:

3 left

💡 Hint

Common Mistakes

Using trimMargin() without margin prefix causes no effect.

Using trim() only removes spaces at start and end of whole string.

trimIndent() correctly removes the common leading spaces from all lines in the multiline string.

4fill in blank

hard

Fill both blanks to create a multiline string and remove its indentation.

Kotlin

val poem = [1]
    Roses are red,
    Violets are blue.
""".[2]()

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

A"""

BtrimMargin

CtrimIndent

Dtrim

Attempts:

3 left

💡 Hint

Common Mistakes

Using trimMargin() without margin prefix.

Not using triple quotes for multiline strings.

Start the string with triple quotes """ and use trimIndent() to remove indentation.

5fill in blank

hard

Fill all three blanks to create a multiline string, trim indentation, and print it.

Kotlin

fun main() {
    val quote = [1]
        Be yourself;
        everyone else is already taken.
    """.[2]()
    println([3])
}

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

A"""

BtrimIndent

Cquote

DtrimMargin

Attempts:

3 left

💡 Hint

Common Mistakes

Using trimMargin() without margin prefix.

Printing the string literal instead of the variable.

Not using triple quotes for multiline strings.

Use triple quotes """ to start the string, trimIndent() to remove indentation, and print the variable quote.

Practice

1. What does the trimIndent() function do when used with multiline strings in Kotlin?

easy

A. It converts the string to uppercase.

B. It adds extra spaces at the beginning of each line.

C. It splits the string into a list of lines.

D. It removes the common leading whitespace from each line.

Solution

1. Step 1: Understand the purpose of trimIndent()

   The function trimIndent() removes the common leading whitespace from every line in a multiline string.

2. Step 2: Effect on multiline strings

   This makes the string output aligned neatly without extra indentation caused by code formatting.

3. Final Answer:

   It removes the common leading whitespace from each line. -> Option D

4. Quick Check:

   trimIndent() = removes leading spaces [OK]

Hint: trimIndent() cleans leading spaces for neat multiline strings [OK]

Common Mistakes:

• Thinking trimIndent() adds spaces instead of removing
• Confusing trimIndent() with uppercase conversion
• Assuming trimIndent() splits strings into lines

2. Which of the following is the correct syntax to create a multiline string with trimmed indentation in Kotlin?

easy

A. val text = """Hello\nWorld""".trimIndent()

B. val text = "Hello\nWorld".trimIndent()

C. val text = '''Hello\nWorld'''.trimIndent()

D. val text = ""Hello\nWorld"".trimIndent()

Solution

1. Step 1: Identify multiline string syntax

   Kotlin uses triple double quotes """ to create multiline strings.

2. Step 2: Apply trimIndent() correctly

   Calling trimIndent() on the multiline string removes common leading spaces.

3. Final Answer:

   val text = """Hello\nWorld""".trimIndent() -> Option A

4. Quick Check:

   Triple quotes + trimIndent() = correct syntax [OK]

Hint: Use triple quotes """ for multiline strings with trimIndent() [OK]

Common Mistakes:

• Using single quotes instead of triple quotes
• Trying to trimIndent() on a normal string
• Wrong quote count causing syntax errors

3. What will be the output of the following Kotlin code?

val text = """
    Kotlin
    is
    fun
""".trimIndent()
println(text)

medium

A. Kotlin
is
fun

B. Kotlin
is
fun

C. Kotlin
is
fun

D. Kotlin is fun

Solution

1. Step 1: Analyze the multiline string with indentation

   The string has 4 spaces before each line inside the triple quotes.

2. Step 2: Effect of trimIndent()

   trimIndent() removes the common 4-space indentation from all lines.

3. Final Answer:

   Kotlin is fun -> Option C

4. Quick Check:

   trimIndent() removes leading spaces = clean lines [OK]

Hint: trimIndent() removes common leading spaces from all lines [OK]

Common Mistakes:

• Expecting original indentation to remain
• Confusing trimIndent() with trim() which removes only ends
• Thinking output is a single line string

4. Identify the error in this Kotlin code snippet using multiline strings and trimIndent():

val message = """
  Hello
    World
"".trimIndent()
println(message)

medium

A. Missing one double quote in the closing triple quotes.

B. The closing triple quotes should be """ not "".

C. No error; code runs and prints correctly.

D. Incorrect use of trimIndent() on a non-multiline string.

Solution

1. Step 1: Check triple quote syntax

   Multiline strings require triple double quotes """ at start and end.

2. Step 2: Identify the closing quotes

   The code uses only two double quotes "" at the end, which is invalid syntax.

3. Step 3: Correct the closing quotes

   It should be """ to properly close the multiline string.

4. Final Answer:

   The closing triple quotes should be """ not "". -> Option B

5. Quick Check:

   Triple quotes must match at start and end [OK]

Hint: Always close multiline strings with triple quotes """ [OK]

Common Mistakes:

• Using two quotes instead of three to close multiline strings
• Assuming trimIndent() fixes quote errors
• Confusing trimIndent() with trimming quotes

5. You want to create a multiline string in Kotlin that shows a list of fruits without extra indentation in the output. Which code snippet correctly achieves this using trimIndent()?

hard

A. val fruits = """
- Apple
- Banana
- Cherry
""".trimIndent()
println(fruits)

B. val fruits = """
- Apple
- Banana
- Cherry
""".trimIndent()
println(fruits)

C. val fruits = """
- Apple
- Banana
- Cherry
""".trimIndent()
println(fruits)

D. val fruits = "- Apple\n- Banana\n- Cherry".trimIndent()
println(fruits)

Solution

1. Step 1: Understand trimIndent() effect on indentation

   trimIndent() removes the common leading spaces from all lines, aligning text properly.

2. Step 2: Check each option's indentation

   val fruits = """ - Apple - Banana - Cherry """.trimIndent() println(fruits) has consistent 4-space indentation on each line, so trimIndent() will remove it neatly.

3. Step 3: Evaluate other options

   val fruits = """ - Apple - Banana - Cherry """.trimIndent() println(fruits) has uneven indentation, so trimIndent() removes nothing and leaves extra spaces on some lines. val fruits = """ - Apple - Banana - Cherry """.trimIndent() println(fruits) has uneven indentation, so trimIndent() won't align all lines properly. val fruits = "- Apple\n- Banana\n- Cherry".trimIndent() println(fruits) is a normal string, trimIndent() has no effect.

4. Final Answer:

   val fruits = """ - Apple - Banana - Cherry """.trimIndent() println(fruits) -> Option A

5. Quick Check:

   Consistent indentation + trimIndent() = neat output [OK]

Hint: Use consistent indentation inside triple quotes before trimIndent() [OK]

Common Mistakes:

• Using uneven indentation causing partial trimming
• Not using triple quotes for multiline strings
• Expecting trimIndent() to fix uneven spaces