Goal:
-----
I want to create x number of groups. These groups will have a list of
servers. I split these servers in groups by name. What I would like is for
this function to be dynamic. I hope the example will make my goal clear.

Example:
---------
This is a very simple example... I am looking at creating 40+ groups... it
gets to be ALOT of duplicate code.



# This is what works now
Function Create-Groups {
param([system.array]$servers)
# this is where I would like to be more dynamic
$list1 = @()
$list2 = @()
$list3 = @()
$list4 = @()
$list5 = @()
foreach($server in $servers) {
if ($Server -match ".*ver1.$") {$list1 += $server}
elseif($Server -match ".*ver2.$") {$list2 += $server}
elseif($Server -match ".*ver3.$") {$list3 += $server}
elseif($Server -match ".*ver4.$") {$list4 += $server}
elseif($Server -match ".*ver5.$") {$list5 += $server}
}
# This is where I would like to be more dynamic
$global:group1 = $list1
$global:group2 = $list2
$global:group3 = $list3
$global:group4 = $list4
$global:group5 = $list5
}

Problem:
---------
Now if I wanted to make 10 groups instead of 5... I have create 5 more
arrays and global variables. I would like to do something like:

# this of course fails... is there a way I can do this?
$i = 1
while($i -lt 21) {
$list$i = @()
++$i
}

"Brandon Shell" wrote:
> # this of course fails... is there a way I can do this?
> $i = 1
> while($i -lt 21) {
> $list$i = @()
> ++$i
> }
You can use "Invoke-Expression" cmdlet to create variables dynamially

foreach ($i in (1..21)) {
Invoke-Expression ('$`{list' + $i + '`} = @()')
}

Have fun~
--
Sung M Kim

Please don''t bother me with spam...

Thanks
"Sung M Kim" <SungMKim@discussions.microsoft.com> wrote in message
news:0A7D67F1-A612-46C3-A7CC-A5075012EFB0@microsoft.com...
> "Brandon Shell" wrote:
>> # this of course fails... is there a way I can do this?
>> $i = 1
>> while($i -lt 21) {
>> $list$i = @()
>> ++$i
>> }
> You can use "Invoke-Expression" cmdlet to create variables dynamially
>
> foreach ($i in (1..21)) {
> Invoke-Expression ('$`{list' + $i + '`} = @()')
> }
>
> Have fun~
> --
> Sung M Kim
>
> Please don''t bother me with spam...
>

Yes, it is possible, but I would double think before using this approach. I
am just curious, why not to use, say, global hash tables with keys like
'ver1.$', 'ver2.$', etc. for servers, lists etc.?

--
Thanks,
Roman

Because I want to pipe the list to functions.

Example:
group1 | Check-Something | fix-problem

"Roman Kuzmin" <RomanKuzmin@discussions.microsoft.com> wrote in message
news:EDCBA044-6C0B-4361-96CC-37961F4B6589@microsoft.com...
> Yes, it is possible, but I would double think before using this approach.
> I
> am just curious, why not to use, say, global hash tables with keys like
> 'ver1.$', 'ver2.$', etc. for servers, lists etc.?
>
> --
> Thanks,
> Roman
>

I definitely do not criticize.

Suppose your lists are in a hash $groups with keys like 1, 2, ‘ver5.$’ and
etc. For any <key>, i.e. group, you can do this:

$group[<key>] | Check-Something | fix-problem

No problem. For example if you want to process 3 groups 1, 2, ‘ver5.$’:

1, 2, ‘ver5.$’ | % {$group[$_]} | Check-Something | fix-problem

Suppose now a list of groups for a particular task is defined as an array
$ToDo; it is as easy as before:

$ToDo | % {$group[$_]} | Check-Something | fix-problem

Do you know how to do the same with your approach? If you know the answer
and like it then this approach is good for you.

--
Thanks,
Roman

Brandon Shell wrote:
> Goal:
> -----
> I want to create x number of groups. These groups will have a list of
> servers. I split these servers in groups by name. What I would like is for
> this function to be dynamic. I hope the example will make my goal clear.

I wouldn't use invoke-expression. It's somewhat ugly.

I'd use the cmdlets designed for the purpose: new-variable,
set-variable, and get-variable (nv, sv, and gv).

nv "var.$foo"
sv "var.$foo" "value $i"
gv "var.$foo"

In place of string interpolation, you can use subexpressions:

nv ("var." + $nextVar)

You can also specify the value at creation time:

nv name value

-- Adam

Sung M Kim wrote:
> "Brandon Shell" wrote:
>> # this of course fails... is there a way I can do this?
>> $i = 1
>> while($i -lt 21) {
>> $list$i = @()
>> ++$i
>> }
> You can use "Invoke-Expression" cmdlet to create variables dynamially
>
> foreach ($i in (1..21)) {
> Invoke-Expression ('$`{list' + $i + '`} = @()')
> }

Another, simpler, way is to use the new-variable cmdlet:

foreach ($i in (1..21)) {
new-variable "list$i" @()
}

I will take a look. You way does have some potential. My only concern is
that most of scripts are wrappers for people... that... hmmm... are less
than brilliant.

Im trying to keep the input as little and brainless as possible.

"Roman Kuzmin" <RomanKuzmin@discussions.microsoft.com> wrote in message
news:165DEFC0-FACA-4258-A531-A44ADE1FD1E6@microsoft.com...
>I definitely do not criticize.
>
> Suppose your lists are in a hash $groups with keys like 1, 2, 'ver5.$' and
> etc. For any <key>, i.e. group, you can do this:
>
> $group[<key>] | Check-Something | fix-problem
>
> No problem. For example if you want to process 3 groups 1, 2, 'ver5.$':
>
> 1, 2, 'ver5.$' | % {$group[$_]} | Check-Something | fix-problem
>
> Suppose now a list of groups for a particular task is defined as an array
> $ToDo; it is as easy as before:
>
> $ToDo | % {$group[$_]} | Check-Something | fix-problem
>
> Do you know how to do the same with your approach? If you know the answer
> and like it then this approach is good for you.
>
> --
> Thanks,
> Roman
>

"Jouko Kynsijärvi" wrote:
> Another, simpler, way is to use the new-variable cmdlet:
>
> foreach ($i in (1..21)) {
> new-variable "list$i" @()
> }

That's brilliant
This is the second time that I overlooked "*-Variable" cmdlets... as was the
case when I needed to create a constant variable ;p
--
Sung M Kim