Inspection Details

ParameterCanBeByVal

Summary
Flags parameters that are passed by reference (ByRef), but could be passed by value (ByVal).
Reasoning
Explicitly specifying a ByVal modifier on a parameter makes the intent explicit: this parameter is not meant to be assigned. In contrast, a parameter that is passed by reference (implicitly, or explicitly ByRef) makes it ambiguous from the calling code's standpoint, whether the procedure might re-assign these ByRef values and introduce a bug.
The following code example(s) would trigger this inspection:

Public Sub DoSomething(ByVal foo As Long, bar As Long)
    Debug.Print foo, bar
End Sub

The following code example(s) would not trigger this inspection:

Option Explicit
Public Sub DoSomething(ByVal foo As long, ByRef bar As Long)
    bar = foo * 2 ' ByRef parameter assignment: passing it ByVal could introduce a bug.
    Debug.Print foo, bar
End Sub


Back to List