What differentiates Server/Client actions set as Function from regular actions?

The distinction between Server/Client actions set as Function and regular actions primarily lies in their output capabilities. Specifically, actions designated as Function can only have one output parameter, which is a defining characteristic. This restriction allows them to be incorporated seamlessly within expressions, making it possible for developers to call these functions directly in an expression context.

Regular actions, on the other hand, do not have this limitation and can return multiple output parameters, which makes them suitable for different use cases outside of simple expressions. The single output parameter for Function actions simplifies their design and usage in scenarios where a single value is needed, promoting clarity in the code's flow.

Furthermore, Function actions are capable of being utilized in expressions, thereby enabling their output to be utilized in a more dynamic manner within the logic of the application. Other options relate to functionalities or capabilities that do not align with the core definition of what distinguishes Function actions in terms of their structure and usability in the OutSystems platform.