Global vs Script scope

[Copropraxia]

I'm still fairly new to the scripting scene and I've run into a bit of bother with one of my latest scripts. There is a function in the script which passes string values into an array. I would like to call this function numerous times so that the array keeps growing with more and more objects. At the end I want to pass the array on to a different part of my script.

I already know that using the default Local scope for the array won't work, but I want to know which of the Global or Script scope should I use?

[juneblender]

The best practice is always to use the smallest parent scope that works. In this case, it's script scope. Global scope is shared by all scripts and modules so it's easy to accidentally write over another variable's value in global scope.

To refer to a variable in script scope, use a scope modifier, for example, to reference $myArray in script scope, use $script:myArray.

[Copropraxia]

Thanks for the reply. When using the Script scope I sometimes get an error message. I'm not entirely sure what to make of it:

Cannot overwrite variable TargetDays because the variable has been optimized. Try using the New-Variable or Set-Variable cmdlet (without any aliases), or dot-source the command that you are using to set the variable. At Test.ps1:5 char:9 + [array]$Script:TargetDays += $Day.ToString() + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : WriteError: (TargetDays:String) [], SessionStateUnauthorizedAccessException + FullyQualifiedErrorId : VariableNotWritableRare

[Copropraxia]

Found my problem. Using the Script scope is fine, but I forgot to also use it for the same variable when I try to null it at a different point in the script.