This information is part of the Modelica Standard Library maintained by the Modelica Association.
Annotation for code generation (hide result)
annotation"(" HideResult "=" ( false | true ) ")
HideResult = true defines that the model developer proposes to not show the simulator results of the corresponding component [e.g., it will not be possible to plot this variable].
HideResult = false defines that the developer proposes to show the corresponding component [if a variable is declared in a protected section, a tool might not include it in a simulation result. By setting HideResult = false, the modeler would like to have the variable in the simulation result, even if in the protected section].
HideResult is for example used in the connectors of the Modelica.StateGraph library to not show variables to the modeler that are of no interest to him and would confuse him.