- Although duplicate port names do not necessarily constitute a modeling error, there can be some side-effects if more than one input or more than one output on the same object have been assigned the same name. Because duplicate ports names are sometimes desirable for their side effects, and internally eXpress has no problem distinguishing between them, no error message will be generated when this situation occurs. This situation can be easily identified, however, in Grid View, where port abbreviations are listed in red when another port on the same object has been assigned the same abbreviation.
There are several ways in which duplicate port names can occur:
when, while naming ports, the same abbreviation is explicitly assigned to two ports on the same object
when nets are named (without ports having first been named) and two of an object's ports are connected to the same net
as an unintended side effect of combining these two port naming methods (explicit port-naming and net-naming)
when ports are not named (the empty abbreviations are considered to be duplicates)
Duplicate Input Port Names
There is no effect upon analyses when multiple input ports on the same object are assigned the same abbreviation. It may, however, be difficult to define output function dependencies and state control dependencies on these objects, since the two ports will be indistinguishable when listed on the Output Functions and States panels.
Duplicate Output Port Names
Because output function names are automatically derived from the ports for which they are defined, duplicate output port names will, by default, lead to duplicate output function names. Duplicate output port names will have an effect upon diagnostics because duplicate output functions (when they occur on the same object) are considered to be the same function within eXpress analyses.Although there are cases where this behavior is desirable (e.g., simple, passive, bi-directional components), it should be approached with caution.
