Yet another PS object fast comparer (2 editions)

compare-array.ps1

function Compare-Array {
	[CmdletBinding()]
	[alias('Compare-Object2','Compare-ObjectFast')]
	param (
		[Parameter(Position=0)]
		[psobject[]] $ReferenceObject,
		[Parameter(Position=1)]
		[psobject[]] $DifferenceObject,
		[switch] $IncludeEqual,
		[switch] $ExcludeDifferent
	)
	
	if ($DifferenceObject.count -eq 0 -or $ReferenceObject.count -eq 0) {return}

	# Diff index: put the difference array into a hash table
	$DifHash = @{}
	$DifferenceObject.foreach{$DifHash[$_] = 1}

	# Ref index: put the reference array into a hash table
	$RefHash = @{}
	$ReferenceObject.foreach{$RefHash[$_] = 1}

	if ($IncludeEqual) {
		foreach ($item in $ReferenceObject) {
			if ($DifHash.ContainsKey($item)) {
				$DifHash.Remove($item)
				$RefHash.Remove($item)

				[pscustomobject]@{
					InputObject   = $item
					SideIndicator = '=='
				}
			}
		}
	} 
	else {
		foreach ($item in $ReferenceObject) {
			if ($DifHash.ContainsKey($item)) {
				$DifHash.Remove($item)
				$RefHash.Remove($item)
			}
		}
	}

	if (-not $ExcludeDifferent) {
		foreach ($k in $RefHash.Keys) {
			[pscustomobject]@{
				InputObject   = $k
				SideIndicator = '<='
			}
		}
		foreach ($k in $DifHash.Keys) {
			[pscustomobject]@{
				InputObject   = $k
				SideIndicator = '=>'
			}
		}
	}
} # END Compare-Array

function Compare-Array2 {
	[CmdletBinding()]
	param (
		[Parameter(Position=0)]
		[array] $ref,
		[Parameter(Position=1)]
		[array] $dif, 
		[switch] $IncludeEqual,
		[switch] $ExcludeDifferent
	)
	if ($ref.count -eq 0 -or $dif.count -eq 0) {return}
	$difhash = [System.Collections.Generic.HashSet[string]]::new(
		[string[]]$dif,
		[System.StringComparer]::InvariantCultureIgnoreCase # OrdinalIgnoreCase
	)
	$refhash = [System.Collections.Generic.HashSet[string]]::new(
		[string[]]$ref,
		[System.StringComparer]::InvariantCultureIgnoreCase # OrdinalIgnoreCase
	)
	if ($IncludeEqual) {
		$ref.Where({$difhash.Contains($_)}).foreach{
			[pscustomobject]@{
				InputObject   = $_
				SideIndicator = '=='
			}
		}
	}
	if (-not $ExcludeDifferent) {
		$ref.Where({-not $difhash.Contains($_)}).foreach{
			[pscustomobject]@{
				InputObject   = $_
				SideIndicator = '<='
			}
		}
		$dif.Where({-not $refhash.Contains($_)}).foreach{
			[pscustomobject]@{
				InputObject   = $_
				SideIndicator = '=>'
			}
		}
	}
} # END Compare-Array2