Question

I’m writing a PowerShell function, and I want it to return a single Boolean. The problem is that PowerShell will return anything in the pipeline and not just what was explicitly included in the return statement.

Consider the following code.

function getTrue(){
  $testVariable = "test"
  $test
  return $true
}

$answer = getTrue

Write-host $answer

The output of this code is

test True

This returns a System.Object[]. I want to force the return value to be a System.Boolean.

This code works fine if I add a Write-Host:

function getTrue(){
  $testVariable = "test"
  Write-Host $test
  return $true
}

The only problem is that I’m depending on a function that someone else is writing (I can’t modify it), and I can’t gaurantee that they used a Write-Host instead of just leaving the variable on the line by itself.

Is there a way to force the function to only return the value that I want?

Answer 1

Just use Out-Null to suppress unexpected returning:

function getTrue(){
    $test = "test";
    $test | Out-Null;
    return $true;
}

$answer = getTrue
Write-Host $answer

and

function getTrue(){
    $test = "test";
    Write-Host $test | Out-Null;
    return $true;
}

$answer = getTrue
Write-Host $answer