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Gotcha Ignoring unwanted output

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Inspired by 

function bar {
 [System.Collections.ArrayList]$MyVariable = @()
 $MyVariable.Add("a") | Out-Null
 $MyVariable.Add("b") | Out-Null
 $MyVariable
}

The Out-Null is necessary because the .NET ArrayList.Add method returns the number of items in the collection after adding. If omitted, the pipeline would have contained 1, 2, "a", "b"

There are multiple ways to omit unwanted output: 

function bar
{
    # New-Item cmdlet returns information about newly created file/folder
    New-Item "test1.txt" | out-null
    New-Item "test2.txt" > $null
    [void](New-Item "test3.txt")
    $tmp = New-Item "test4.txt"
}

Note: to learn more about why to prefer > $null, see [topic not yet created].

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Return behavior in PowerShell:
* Return behavior in PowerShell
* Early exit
* Gotcha Return in the pipeline
* Return with a value
* Gotcha Ignoring unwanted output
* How to work with functions returns
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