When do simple parenthetical grouping matter in PowerShell code?

Question

When do simple parenthetical grouping matter in PowerShell code?
Here's one example when using parenthesis matters (thanks to Boe Prox for inspiring this example):
<#c:#> 'abc' >xo
<#c:#> gc xo | set-content xo
set-content : The process cannot access the file 'C:\users\larry\documents\windowspowershell\xo' because it is b
used by another process.
At line:1 char:9
+ gc xo | set-content xo
+ ~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [Set-Content], IOException
+ FullyQualifiedErrorId : System.IO.IOException,Microsoft.PowerShell.Commands.SetContentCommand
<#c:#> 'abc' >xo
<#c:#> (gc xo) | set-content xo
<#c:#> type xo
abc
Here's an example of arithmetic expression evaluation and added parenthesis
<#c:#> 10*100+1000
2000
<#c:#> 10*(100+1000)
11000
<#c:#>
Are there other coding examples using PowerShell where adding parenthesis changes the semantics of a statement?

Answer 1

Hi Larry,
In addition,I also find an explanation from other forum may be helpful for you:
In powershell certain types of expressions, when used as statements, are not displayed. Voidable statements include assignments and the increment/decrement operators. When they are used in an expression, they return a value, but when they’re used as a standalone
statement, they return no value. It is very well explained in Windows Powershell in Action by Bruce Payette.
The increment and decrement operators were almost not included in PowerShell because they introduced a problem. In languages such as C and C#, when you use one of these operators as a statement: $a++ nothing is displayed. This is because statements
in C and C# don’t return values. In PowerShell, however, all statements return a value. This led to confusion. People would write scripts like this:
$sum=0
$i=0
while ($i -lt 10) { $sum += $i; $i++ }
$sum
and be surprised to see the numbers 1 through 10 displayed. This was because $a++ returned a value and PowerShell was displaying the results of every statement. This was so confusing that we almost removed these operators from the language. Then
we hit on the idea of a voidable statement. Basically, this means that certain types of expressions, when used as statements, are not displayed. Voidable statements include assignments and the increment/decrement operators. When they are used in an expression,
they return a value, but when they’re used as a standalone statement, they return no value. Again, this is one of those details that won’t affect how you use PowerShell other than to make it work as you expect. (source: Windows Powershell in Action).
Reference:
Why it needs an extra pair of bracket?
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