What does the expression widget in OutSystems do?

The expression widget in OutSystems is designed to evaluate and display dynamic content at run time. This means it can perform calculations, incorporate variables, or pull data from different sources during the execution of the application. When the application is running, the expression widget can show real-time values that change based on user interactions or other conditions, thus offering a responsive user interface that reflects the current state of the application.

For example, if you have a variable that holds a user's name or a calculated total based on user inputs, using an expression widget allows that information to be presented dynamically as the user interacts with the application. This functionality is essential for creating a dynamic user experience, as it responds to the contextual data available at the moment the user views the content.

In contrast, the other options do not accurately represent how the expression widget functions. Static text is limited to fixed values that do not change, while displaying text at compile time means the value is determined before the application is run, which doesn't leverage run-time data. Lastly, while error messages might be displayed in various widgets designed for that purpose, the expression widget itself is not restricted to showing only error messages; it can display a wide range of data types and messages based on the logic defined in your application.