Public Sub aaa()

Dim aa As String, bb As String, cc As Long

bb = ″b″
cc = 2
aa = bbb(bb, cc)

End Sub

Public Function bbb(ByRef b As String, ByVal c As Long)As String

(中略)

End Sub

ってやるとFunction入る前にエラーで弾かれて
aa = bbb(bb, (cc))ってやったりaa = bbb(bb, cc + 1)ってやったりすると通るんだがおま環だった？