In OutSystems, what must every variable declare?

In OutSystems, every variable must declare its data type. This requirement is essential because the data type defines the kind of data that the variable can hold, such as integers, strings, booleans, or more complex objects. By specifying the data type, the OutSystems platform can manage memory efficiently and provide the necessary operations and functions relevant to that type of data.

Understanding the data type is crucial for ensuring that the application behaves as expected, especially when performing operations like calculations, comparisons, or string manipulations. This helps prevent runtime errors and unforeseen behaviors in the application, contributing to writing robust and maintainable code.

While visibility, ownership, and usage are important aspects of variable management in programming, they are not mandatory declarations in OutSystems. For instance, while you might set these attributes for specific purposes in your application logic, the primary requirement at the moment of variable declaration is establishing its data type.