Error Insight
From RadPHP XE2 Documentation
Error Insight is a feature that performs syntax checking while you type code. Error Insight shows the errors on the Structure Pane and also underlines in red the token that is causing problems.
This prevents you from running or uploading to your server php scripts with syntax errors and keeps you focused in your code.
When the Structure Pane shows an error, double clicking on it, will focus the line where the problem is located.
