Enum ArgumentPassing
How the argument of a parameter is passed (MS-VBAL §5.3.1.11), as far as the declarations and the argument as it is written decide it.
public enum ArgumentPassing
Fields
Omitted = 3An
Optionalparameter the call gives no argument: its declared default, or what an omitted argument of its type is.ParamArray = 2A
ParamArrayparameter: what the trailing positional arguments are collected into (Elements).Reference = 1A
ByRefparameter whose argument may be a variable - a name, an element of an array, a member of an object, a field of a record, what is bound late: the parameter is a second name for it when it is a variable of the parameter's declared type, which is the call's to find out, and a copy of its value otherwise.Value = 0Let-coerced to the parameter's declared type, into a variable of the activation's own: a
ByValparameter, and aByRefone whose argument is no variable - a literal, an operation, a call, an expression in parentheses.