$MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Microsoft news and tips » $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Mon, 21 Apr 2008 03:10:28 GMT

PingBack from http://microsoftnews.askpcdoc.com/?p=3373

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Roman Kuzmin — Mon, 21 Apr 2008 15:05:34 GMT

It is a great idea to promulgate this. It seems to me that most of PowerShell users including fanatics never heard about this technique.

Will it work in the same way for script cmdlets?

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

PowerShellTeam — Mon, 21 Apr 2008 15:33:23 GMT

> Will it work in the same way for script cmdlets?

It doesn't right now but it should.

Jeffrey Snover [MSFT]

Windows Management Partner Architect

Visit the Windows PowerShell Team blog at: http://blogs.msdn.com/PowerShell

Visit the Windows PowerShell ScriptCenter at: http://www.microsoft.com/technet/scriptcenter/hubs/msh.mspx

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Don Jones — Tue, 22 Apr 2008 16:22:41 GMT

Pingback from http://blog.sapien.com/index.php/2008/04/22/scriptblocks-as-cmdlet-parameter-values/

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

karl prosser — Tue, 22 Apr 2008 19:02:59 GMT

this here therefore sets the parameter to a different value each time an item comes through the pipeline despite the fact that the cmdlet gets called only once?

Thus it will only behave correctly for cmdlets that read the parameter each item, rather than just reading it in the beginprocess section?

-Karl

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

vbNullString — Tue, 22 Apr 2008 19:41:28 GMT

I have been personally evangelizing PowerShell at work and also on my blog for a while now. The more I dig into PowerShell, the more I realize how powerful it is and it will change the face of shell world.

So I made a PowerShell cap.

http://www.devslife.com/2008/04/20/powershell帽/

Though I blog in Japanese, I live near Seattle. If you see me wearing the cap, please say hi to me! :)

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Maximilian Hänel — Wed, 23 Apr 2008 12:30:23 GMT

@karl

I haven't tried it, but I don't think scriptblock parameters are much different from pipline parameters. So I guess you have to re-read the parameter for each item in the pipline.

The alternative would be that your CmdLets Begin/Bla/Process methods are called for each pipline item in the case of scriptblock parameters being present. But then your CmdLet would behave rather different in those two scenarios (think about measure-object), so I don't think it works that way.

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Oisin Grehan — Thu, 24 Apr 2008 03:46:24 GMT

uh.. never heard of this.. madness. Does this work for v1.0 ? (only have v2 ctp here).

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

PowerShellTeam — Thu, 24 Apr 2008 06:12:40 GMT

> Does this work for v1.0 ?

Yes.

Jeffrey Snover [MSFT]

Windows Management Partner Architect

Visit the Windows PowerShell Team blog at: http://blogs.msdn.com/PowerShell

Visit the Windows PowerShell ScriptCenter at: http://www.microsoft.com/technet/scriptcenter/hubs/msh.mspx

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

sbq — Sat, 26 Apr 2008 02:48:06 GMT

This sounds a lot like what I did with my AD mail enabled object dump scripts. Being an old crusty Exchange admin I've learned that it's nice to have a directory dump that you can refer back to from time to time, I came up with something like this when Powershell came out and I started using it (abbreviated and sanitized):

$date = get-date -format yyyyMMdd

$fname = "userDump-" + $date + ".csv"

$domain = New-Object System.DirectoryServices.DirectoryEntry

$DN1 = (get-content Z:\Directory\UserDump\DN-import.txt)

$DN2 = $DN1 | foreach {

$domain.PSBase.Children.find($_)

}

filter Format-DumpADUser {

$_ | select @{name='distinguishedName';Expression={$_.distinguishedName} },

@{ name='homeMDB'; Expression={$_.homeMDB} },

@{ name='displayName'; Expression={$_.displayName} },

@{ name='mail'; Expression={$_.mail} },

@{ name='proxyAddresses'; Expression={$_.proxyAddresses} },

@{ name='memberOf'; Expression={$_.memberOf} },

@{ name='whenChanged'; Expression={$_.whenChanged} },

@{ name='whenCreated'; Expression={$_.whenCreated} },

@{ name='extensionAttribute1'; Expression={$_.extensionAttribute1} },

@{ name='mailNickname'; Expression={$_.mailNickname} },

@{ name='mDBUseDefaults'; Expression={$_.mDBUseDefaults} },

@{ name='mDBOverQuotaLimit'; Expression={$_.mDBOverQuotaLimit} },

@{ name='mDBStorageQuota'; Expression={$_.mDBStorageQuota} }

}

$DN2 | foreach {

$_.PSBase.Children

} | Format-DumpADUser | export-csv -NoTypeInformation Z:\Directory\Archive\$fname

re: $MindWarpingPower = $Cmdlets + $ScriptBlock_Parameters

Shay — Mon, 28 Apr 2008 11:35:23 GMT

I have a case where a scriptblock parameter is evaluated literally:

Get-DistributionGroup | Set-DistributionGroup -DisplayName {"~$($_.name)"}

The name of the groups are updated with: "~$($_.name)".

Could it be because -DisplayName is a dynamic parameter?

Here is the The relevant trace-command output:

DEBUG: ParameterBinding Information: 0 : BIND NAMED cmd line args

[Set-DistributionGroup]

DEBUG: ParameterBinding Information: 0 : BIND POSITIONAL cmd line args

[Set-DistributionGroup]

DEBUG: ParameterBinding Information: 0 : BIND cmd line args to DYNAMIC

parameters.

DEBUG: ParameterBinding Information: 0 : DYNAMIC parameter object:

[Microsoft.Exchange.Data.Directory.Management.DistributionGroup]

DEBUG: ParameterBinding Information: 0 : BIND NAMED args to DYNAMIC

parameters

DEBUG: ParameterBinding Information: 0 : BIND arg ["~$($_.name)"]

to parameter [DisplayName]

DEBUG: ParameterBinding Information: 0 : COERCE arg type

[System.Management.Automation.ScriptBlock]

[System.String]

DEBUG: ParameterBinding Information: 0 : CONVERT arg type

to param type using

LanguagePrimitives.ConvertTo

DEBUG: ParameterBinding Information: 0 : CONVERT SUCCESSFUL

using LanguagePrimitives.ConvertTo:

["~$($_.name)"]

DEBUG: ParameterBinding Information: 0 : BIND arg

["~$($_.name)"]

to param [DisplayName] SUCCESSFUL

-----

Shay Levi

$cript Fanatic

http://scriptolog.blogspot.com