Private/Invoke-NullCoalescing.ps1
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<#
.SYNOPSIS Returns the first argument -ne $null, or $null if all arguments are $null. Similar to the C# ?? operator e.g. name = value ?? String.Empty .NOTES This was extracted from the PSCX module for internal use in this module without requiring a dependency on PSCX. .LINK https://github.com/flofreud/pscx/blob/master/about_Pscx.help.txt .LINK https://msdn.microsoft.com/en-us/library/ms173224.aspx .LINK https://msdn.microsoft.com/en-us/library/ms173224.aspx #> Function Invoke-NullCoalescing { param( [Parameter(Mandatory, Position=0)] [AllowNull()] [scriptblock] $PrimaryExpr, [Parameter(Mandatory, Position=1)] [scriptblock] $AlternateExpr, [Parameter(ValueFromPipeline, ParameterSetName='InputObject')] [psobject] $InputObject ) Process { if ($pscmdlet.ParameterSetName -eq 'InputObject') { if ($PrimaryExpr -eq $null) { Foreach-Object $AlternateExpr -InputObject $InputObject } else { $result = Foreach-Object $PrimaryExpr -input $InputObject if ($null -eq $result) { Foreach-Object $AlternateExpr -InputObject $InputObject } else { $result } } } else { if ($PrimaryExpr -eq $null) { &$AlternateExpr } else { $result = &$PrimaryExpr if ($null -eq $result) { &$AlternateExpr } else { $result } } } } } |