Return values in PowerShell - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this PowerShell function call?

Consider the following PowerShell function and its call. What will be the output?

PowerShell

function Get-Sum {
  param($a, $b)
  return $a + $b
}
Get-Sum 3 4

A Error: Missing return value

B 3 4

C 7

D 34

💡 Hint

Remember that return outputs the result of the expression.

The function adds two numbers and returns the sum. Calling Get-Sum 3 4 returns 7.

💻 Command Output

intermediate

What does this PowerShell script output?

What is the output of this script?

PowerShell

function Test-Return {
  Write-Output "Start"
  return "Returned Value"
  Write-Output "End"
}
Test-Return

A

Start
End

B

Start
Returned Value

C

Returned Value
End

D

Start
Returned Value
End

💡 Hint

Return stops the function immediately.

The function writes "Start", then returns "Returned Value" and stops. "End" is never printed.

📝 Syntax

advanced

Which option correctly returns multiple values from a PowerShell function?

You want a function to return multiple values as an array. Which code does this correctly?

PowerShell

function Get-Values {
  # Return multiple values here
}

A return 1, 2, 3

B return @(1, 2, 3)

C return [1, 2, 3]

D return {1, 2, 3}

💡 Hint

PowerShell can return multiple objects separated by commas.

Using commas returns multiple objects. @(...) creates an array but return 1,2,3 returns three objects which PowerShell collects as an array.

🔧 Debug

advanced

Why does this function not return the expected value?

This function is supposed to return the square of a number but returns nothing. Why?

PowerShell

function Get-Square {
  param($x)
  $x * $x
}
$result = Get-Square 5
Write-Output $result

A Because PowerShell functions return the last output automatically, so it should work.

B Because the expression $x * $x is not outputted or returned.

C Because the function lacks an explicit return statement.

D Because the function parameter is missing a type declaration.

💡 Hint

PowerShell functions output the last expression automatically.

PowerShell functions return the output of the last expression automatically, so $x * $x is returned without needing 'return'.

🚀 Application

expert

What is the output of this PowerShell script with multiple return statements?

Analyze this script and select the output it produces.

PowerShell

function Test-MultiReturn {
  param($val)
  if ($val -lt 5) {
    return "Less than 5"
  } elseif ($val -eq 5) {
    return "Equal to 5"
  }
  return "Greater than 5"
}
Test-MultiReturn 5

A Less than 5

B Greater than 5

C No output

D Equal to 5

💡 Hint

Check the condition that matches the input value.

The input is 5, so the elseif condition matches and returns "Equal to 5".

Practice

1. What does the return keyword do in a PowerShell function?

easy

A. It prints a message to the screen.

B. It sends a value back to the place where the function was called.

C. It stops the script from running completely.

D. It creates a new variable inside the function.

Solution

1. Step 1: Understand the purpose of return

   The return keyword in PowerShell is used inside a function to send a value back to the caller.

2. Step 2: Differentiate from other actions

   It does not stop the entire script, print messages, or create variables; it only sends back a result.

3. Final Answer:

   It sends a value back to the place where the function was called. -> Option B

4. Quick Check:

   Return keyword = sends value back [OK]

Hint: Remember: return sends data back from a function [OK]

Common Mistakes:

• Thinking return stops the whole script
• Confusing return with Write-Host output
• Assuming return creates variables

2. Which of the following is the correct syntax to return a value from a PowerShell function?

easy

A. return $value

B. send $value

C. output $value

D. yield $value

Solution

1. Step 1: Identify the correct keyword for returning values

   In PowerShell, the keyword to return a value from a function is return.

2. Step 2: Check syntax correctness

   The correct syntax is return $value. Other options like send, output, or yield are not valid PowerShell keywords for returning values.

3. Final Answer:

   return $value -> Option A

4. Quick Check:

   Return syntax = return $value [OK]

Hint: Use 'return' keyword to send back values [OK]

Common Mistakes:

• Using non-existent keywords like send or yield
• Omitting the return keyword
• Confusing return with Write-Output

3. What will be the output of this PowerShell code?

function Get-Square {
  param($num)
  return $num * $num
}
$result = Get-Square -num 4
Write-Output $result

medium

A. 8

B. 4

C. 16

D. Error

Solution

1. Step 1: Understand the function logic

   The function Get-Square takes a number and returns its square by multiplying the number by itself.

2. Step 2: Calculate the return value for input 4

   4 multiplied by 4 equals 16, so the function returns 16.

3. Final Answer:

   16 -> Option C

4. Quick Check:

   4 * 4 = 16 [OK]

Hint: Multiply input by itself to find square [OK]

Common Mistakes:

• Returning the input instead of its square
• Confusing multiplication with addition
• Expecting an error due to syntax

4. Identify the error in this PowerShell function that is supposed to return the sum of two numbers:

function Add-Numbers {
  param($a, $b)
  $sum = $a + $b
  Write-Host $sum
}

medium

A. The function does not use the return keyword to send back the sum.

B. The parameters are not declared correctly.

C. The addition operator '+' is invalid in PowerShell.

D. The variable $sum is not assigned properly.

Solution

1. Step 1: Check how the function returns the result

   The function uses Write-Host to display the sum but does not use return to send the value back to the caller.

2. Step 2: Understand the difference between output and return

   Write-Host sends output to the pipeline but does not return a value from the function in the expected way for assignment.

3. Final Answer:

   The function does not use the return keyword to send back the sum. -> Option A

4. Quick Check:

   Return keyword needed to send value back [OK]

Hint: Use return to send values back, not just Write-Host [OK]

Common Mistakes:

• Confusing Write-Host with return
• Thinking parameters are wrong
• Believing '+' is invalid operator

5. You want to create a PowerShell function that returns the first non-empty string from a list of inputs. Which function correctly returns the first non-empty string?

hard

A. function Get-FirstNonEmpty {
param([string[]]$inputs)
return $inputs[0]
}

B. function Get-FirstNonEmpty {
param([string[]]$inputs)
foreach ($item in $inputs) {
if ($item -eq '') { return $item }
}
return $null
}

C. function Get-FirstNonEmpty {
param([string[]]$inputs)
foreach ($item in $inputs) {
if (-not $item) { return $item }
}
return 'empty'
}

D. function Get-FirstNonEmpty {
param([string[]]$inputs)
foreach ($item in $inputs) {
if ($item) { return $item }
}
return ''
}

Solution

1. Step 1: Understand the goal

   The function should return the first string that is not empty or null from the input list.

2. Step 2: Analyze each option

   function Get-FirstNonEmpty { param([string[]]$inputs) foreach ($item in $inputs) { if ($item) { return $item } } return '' } checks if the item is truthy (non-empty), then returns it immediately, else returns empty string if none found. function Get-FirstNonEmpty { param([string[]]$inputs) foreach ($item in $inputs) { if ($item -eq '') { return $item } } return $null } returns empty strings, which is wrong. function Get-FirstNonEmpty { param([string[]]$inputs) foreach ($item in $inputs) { if (-not $item) { return $item } } return 'empty' } returns empty or null values, opposite of requirement. function Get-FirstNonEmpty { param([string[]]$inputs) return $inputs[0] } always returns first item without checking if empty.

3. Final Answer:

   if ($item) { return $item } -> Option D

4. Quick Check:

   Return first truthy string using if ($item) [OK]

Hint: Return first truthy item with if ($item) inside loop [OK]

Common Mistakes:

• Returning empty strings instead of non-empty
• Returning null or empty by mistake
• Not checking items before returning