Objects returned from functions??

Heya,

I have one function that is modifying XMLElement and then returns this
element to main function. But somehow (probably some behavior of PowerShell
I am not aware of) is changing type of that object...

Function (it's pretty big):
Write-Host "In Function " $Container.GetType()
Return $Container

Main script:
$Container = Load-Container($(Join-Path $Job.FullName $Container.Name))
Write-Host "After function " $Container.GetType()

To me it makes complete sense, however it doesn't work as expected

This is output:
In Function System.Xml.XmlElement
After function System.Object[]

I read at Keith's blog about returning values:
http://keithhill.spaces.live.com/blo...?wa=wsignin1.0

How are you using functions in that case????

As a workaround, I changed my code as follows:

Main script:
Load-Container($(Join-Path $Job.FullName $Container.Name))
Write-Host "After function " $Container.GetType()

Function:
Set-Variable -Scope 1 -Name Container -Value $Container
#Return [xml.xmlelement]$Container

This works fine, however I don't really like it. Any better idea how to
handle such functions? I know that Write-Host doesn't modify return from
function, but I will rather stick with my currect solution, which is less
error prone.

Martin

Hmmmm, I was wrong, it doesn't work:
Set-Variable : Exception retrieving string: "Cannot find an overload for
"XmlNode" and the argument count: "3"."
At
C:\Links\HDDs\DevHDD\WorkingProjects\S4Maintenance\Runtime\CoreFunctions.ps1:96
char:15
+ Set-Variable <<<< -Scope 1 -Name Container -Value
$Container -Force




"Martin Zugec" <martin.zugec@xxxxxx> wrote in message
news:eq9ynwc3IHA.4500@xxxxxx

Appears to be bug:

WORKS
$Script:Container = $Container

DOESN'T WORK
Set-Variable -Scope 1 -Name Container -Value $Container -Force

DOESN'T WORK
Set-Variable -Scope Script -Name Container -Value $Container -Force

It appears as bug in Set-Variable, or am I wrong??

Martin

"Martin Zugec" <martin.zugec@xxxxxx> wrote in message
news:%23F42t2c3IHA.1428@xxxxxx

Hi Martin,
Please run your function and let the return values display on the console.
Paste it here or check to see whether or not there is some unexpected object
in the output.
Powershell don't need to return object manually, it will do that by itself.
But this behavior sometimes causes some bugs.

Best regards,
Tao Ma


"Martin Zugec" <martin.zugec@xxxxxx>
??????:uRNN09c3IHA.2348@xxxxxx

Two examples:

FUNCTION FAILED
[CriticalError] Container LogoffUsers is missing container.xml file

FUNCTION OK
[Information] Container location set to
C:\Links\HDDs\DevHDD\WorkingProjects\S4Maintenance\Examples\Jobs\OnDemandMainten
ance\RebootServer
[Information] Container name: Reboot server
[Information] Container description: All servers that enters this container
are automatically rebooted
[Information] Is terminator: false
[Information] Is static: false
[Information] Objects timeout: 30
[Information] Default pipe after timeout: Failed
[Information] Required maintenance version: 1
[Information] Inherited from object: Reboot server with version 1
[Information] Loading target containers
[Information] Found 3 containers that RebootServer depends on

All Information\CriticalError are displayed using Write-Host... As I said, I
checked that object that is returned is correct type inside function (I do
..GetType() one line above Return $Container), however when returned it is
immediately changed to System.Object

Right now it works for me. Question is how to you handle complex function
(when you cannot be sure that Return $Object will return $Object) and
whether that problem I encountered is caused by bug in Set-Variable.

Martin

"Tao Ma" <feng_eden@xxxxxx> wrote in message
news:uFqG7Rd3IHA.3348@xxxxxx

Hmmmmmm, I have a strange feeling that "return" is in fact only "break
function" and not return in terms of normal .NET programming

Martin


"Martin Zugec" <martin.zugec@xxxxxx> wrote in message
news:%23lob5fd3IHA.5060@xxxxxx

Hi Martin,

The following function will return a object array which contains 1,2,3:
function () {
1
Write-Host '!'
2
Write-Host '!'
return 3
}

I think your function return more things than your expected. So I suspect
that your function returns some unexpected object. I cannot reproduce
Set-Variable bugs in PowerShell v1 and v2 ctp2.

Tao Ma

"Martin Zugec" <martin.zugec@xxxxxx> ????
news:%23lob5fd3IHA.5060@xxxxxx

This is true. There are often many places where things get added that
you don't realise
i.e most collections when you add something to them return an integer index

myarraylist.add("something")
\myarraylist.add("something")

will actually return a 1 and 2
and in those cases you don't want this going into the pipeline so you
have to explicitly consume the result i.e
[void]myarraylist.add("something")


Tao Ma wrote: