A which command implementation in PowerShell

which_command.ps1

Function WhichCommand(
    [String]$cmd
) {
    try {
        $Command = Get-Command -ErrorAction Stop $cmd
    }
    catch {
        Write-Host -ForegroundColor Red ("{0} not found" -f $cmd)
        Return
    }
    if ($Command.CommandType -eq "Alias") {
        Write-Host ("{0}: aliases to {1}" -f $cmd, $Command.Definition.Trim())
    }
    elseif ($Command.CommandType -eq "Function") {
        Write-Host ("{0}: Function {{{1}}}" -f $cmd, $Command.Definition)
    }
    elseif ($Command.CommandType -eq "Cmdlet") {
        Write-Host ("{0}: a Cmdlet in {1}" -f $cmd, $Command.Source.Trim())
    }
    else {
        Write-Host $Command.Source.Trim()
    }
}

Set-Alias which WhichCommand