How to return one and only one value from a PowerShell function?

Question

I\'ve learned from this Stack Overflow question, that PowerShell return semantics are different, let\'s say, from C#\'s return semantics. Quote from the aforementioned quest

Answer 1

PowerShell does pipes awkwardkly. To work around the return value problem and save the pipeline for real data, pass the function a value by reference, that is, an array. The array can be loaded with the value you wish to return. Here's a simple example:

# tp.ps1
#   test passed parameters
#   show that arrays are passed by reference, and can be used to provide
#   return values outside the pipeline
function doprint
{
    process { write-output "value now: $psitem" }
}

function recurse($thing,     $rtx)
{
    $thing++
    if($thing -lt 20) {
        if($thing -eq 15) { $rtx[0] = $thing }
        write-output $thing | doprint
        recurse $thing     $rtx
    }
}

j=0
$rtv=@(4)
recurse $j     $rtv
write-output $rtv[0]