When you’re developing code interactively how often do you set a variable and then display it to test the result? You can do that in one go using variable squeezing.
Normally you’d do:
PS> $test = 1
PS> $test
1
Set the variable and display the contents as two separate actions.
By enclosing the first statement in parentheses you accomplish both tasks
PS> ($test2 = 2)
2
Great for interactive work but you don’t want it in scripts as you’d be getting output every time you set a variable value!
under: PowerShell