Another PowerGUI Script Editor option I would like to highlight – is the ability to clear the PowerShell runspace each time you start debugging a script:
Here’s the rule of thumb on picking the option you need:
Pick “Run all scripts in the same runspace” if you want the editor to behave like a PowerShell command line in which as you execute scripts and commands they leave the variables with their values assigned and available to whatever scripts you execute after that.
Pick “Reset PowerShell runspace each time debugging is started” if you want PowerGUI to completely clear PowerShell and (optionally) re-load your profile each time you start debugging. This basically emulates the situation when you start a new PowerShell window every time before executing a script – completely pristine environment with nothing left from whichever commands and scripts you executed before.
Use whatever model fits best and enjoy your scripting!