what's the meaning of double underscore ($_.value__)?

Today on powershell.com

http://powershell.com/cs/blogs/tips/archive/2011/04/26/dump-enumerations.aspx

I've found this tip

function Get-Enum($name){
        开发者_如何学编程[Enum]::GetValues($name) | Select-Object @{n="Name";e={$_}},@{n="Value";e={$_.value__}} |
        format-table -autosize
    }

Can someone explain me what's the meaning of $_.value__ ? Thanks.

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I would say this is kind of a hacky way to get the underling value of a enum. Here is the related question and answer: What is the purpose of the public "value__" field that I can see in Reflector against my enum?

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I think it is just another property returned by GetValues().