If you want to use Or the comparison will get very long and annoying to maintain if the allowed parameter list increases. So I would use !Contains and list of allowed parameters (or associative array):
Names Default To Here(1);
myFunc = Function({myParameter},
{default local},
ok_parameters = {"Parameter1", "Parameter2"};
If(!Contains(ok_parameters, myParameter),
Return(Eval Insert("^myParameter^ not in list ^ok_parameters^"));
,
Return(Eval Insert("^myParameter^ in list ^ok_parameters^"));
);
);
output = myFunc("Parameter1");
Show(output);
output = myFunc("notParameter1");
Show(output);
But you can use or/and also, below is one example (| means or):
Names Default To Here(1);
myFunc = Function({myParameter},
{default local},
If(!(myParameter == "Parameter1" | myParameter == "Parameter2"),
return(Eval Insert("output some msg"));
);
);
output = myFunc("Parameter1");
show(output);
output = myFunc ("notParameter1");
show(output);
-Jarmo