All the code I search in books and online will do something like this

$OFS = <some character>

but none of them first save the orignal value

The problem I'm having is the default OFS variable seems to be instanciated
on the fly

dir variable:OFS

will return an error stating it doesn't exist nor does the following see it

Get-Variable -Scope global -Name o*

so if you by habit use Set-PSDebug -Strict in your scripts it will error out.



According to About_Automatic_Variables all of these are set by Powershell
while I can see some of the "read-only" type variables being created on the
fly; I don't see why the OFS variable should be.

I would like to keep the user default value for OFS if I need to override
it. so that it can be restored i.e.

$oldOFS = $OFS
set-variable -name oldOFS -value $OFS

I feel like I'm missing something here but I don't see what or how to achive
this short of catching the error.

thx
bob

You can use Test-Path to check if the ofs exist, if so, the PowerShell use
it as delimiter to concatenate the array element.
If it doesn't exist, PowerShell use blank space instead.

You can use Remove-Item variablefs to investigate above hehavior.

Best wishes.

Tao Ma

"Bob Landau" <BobLandau@xxxxxx> дÈëÓʼþ
news:B9F9BCDC-BA13-4A67-A374-9EFBF06103B4@xxxxxx

> All the code I search in books and online will do something like this
>
> $OFS = <some character>
>
> but none of them first save the orignal value
>
> The problem I'm having is the default OFS variable seems to be

instanciated

> on the fly
>
> dir variable:OFS
>
> will return an error stating it doesn't exist nor does the following see

it

>
> Get-Variable -Scope global -Name o*
>
> so if you by habit use Set-PSDebug -Strict in your scripts it will error

out.

>
> According to About_Automatic_Variables all of these are set by Powershell
> while I can see some of the "read-only" type variables being created on

the

> fly; I don't see why the OFS variable should be.
>
> I would like to keep the user default value for OFS if I need to override
> it. so that it can be restored i.e.
>
> $oldOFS = $OFS
> set-variable -name oldOFS -value $OFS
>
> I feel like I'm missing something here but I don't see what or how to

achive

> this short of catching the error.
>
> thx
> bob

If $OFS doesn't exist and an operation requires it, then the default value
of ' ' (a single space) is used. Depending on what you're doing, the
pattern:

# define an array we'll expand in a string later...
$array = 1,2,3

# expand the array with plus signs separating it...
$s = & { $OFS='+'; "$array" } # set $OFS in a nested scope

may be the easiest solution since you don't have to save OFS - variable
scoping takes care of it for you. Also, just to be clear, $OFS can be any
string. It doesn't need to be a single character:

PS (1) > $array = 1,2,3
PS (2) > & { $OFS = '"+"'; "`"$array`"" }
"1"+"2"+"3"

(And yes - it is a bug that $OFS isn't defined by default...)

-bruce

--
Bruce Payette [MSFT]
Principal Developer, Windows PowerShell
Microsoft Corporation
This posting is provided "AS IS" with no warranties, and confers no rights.

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"Bob Landau" <BobLandau@xxxxxx> wrote in message
news:B9F9BCDC-BA13-4A67-A374-9EFBF06103B4@xxxxxx

> All the code I search in books and online will do something like this
>
> $OFS = <some character>
>
> but none of them first save the orignal value
>
> The problem I'm having is the default OFS variable seems to be
> instanciated
> on the fly
>
> dir variable:OFS
>
> will return an error stating it doesn't exist nor does the following see
> it
>
> Get-Variable -Scope global -Name o*
>
> so if you by habit use Set-PSDebug -Strict in your scripts it will error
> out.
>
> According to About_Automatic_Variables all of these are set by Powershell
> while I can see some of the "read-only" type variables being created on
> the
> fly; I don't see why the OFS variable should be.
>
> I would like to keep the user default value for OFS if I need to override
> it. so that it can be restored i.e.
>
> $oldOFS = $OFS
> set-variable -name oldOFS -value $OFS
>
> I feel like I'm missing something here but I don't see what or how to
> achive
> this short of catching the error.
>
> thx
> bob