PowerShell module for Get/Set/Remove environment variables in Windows

Environment.psm1

function Get-Environment {
  param (
    [parameter(Mandatory=$true)] [ValidateNotNullOrEmpty()]$Name,
    [String] $DefaultValue = $null,
    [ValidateSet("None", "DoNotExpandEnvironmentNames")] [String] $Options = "None"
  )

  ([Microsoft.Win32.Registry]::LocalMachine.OpenSubKey("SYSTEM\CurrentControlSet\Control\Session Manager\Environment", $true)).GetValue($Name, $DefaultValue, $Options)
}

function Set-Environment {
  Param (
    [parameter(Mandatory=$true)] [ValidateNotNullOrEmpty()] [String] $Name,
    [String] $Value = $null,
    [ValidateSet("Binary", "DWord", "ExpandString", "MultiString", "None", "QWord", "String", "Unknown")] [String] $valueKind = "String"
  )

  ([Microsoft.Win32.Registry]::LocalMachine.OpenSubKey("SYSTEM\CurrentControlSet\Control\Session Manager\Environment", $true)).SetValue($Name, $Value, $valueKind)
}

function Remove-Environment {
  param (
    [parameter(Mandatory=$true)] [ValidateNotNullOrEmpty()] [String] $Name,
    [Switch] $throwOnMissingValue = $false
  )

  ([Microsoft.Win32.Registry]::LocalMachine.OpenSubKey("SYSTEM\CurrentControlSet\Control\Session Manager\Environment", $true)).DeleteValue($Name, $throwOnMissingValue)
}