memberaccessexpression.vb

大名鼎鼎的mono是.NET平台的跨平台（支持linux

            If m_Second.IsKeyword AndAlso m_Second.Token.Equals(KS.[New]) Then
                If TypeOf m_First Is InstanceExpression Then
                    Classification = New MethodGroupClassification(Me, m_First, Nothing, Helper.GetInstanceConstructors(T))
                    Return True
                Else
                    Helper.AddError()
                End If
            End If

            Dim members As Generic.List(Of MemberInfo)
            Dim member As MemberCacheEntry

            member = Compiler.TypeManager.GetCache(T).LookupFlattened(Name)
            If member Is Nothing Then
                If Me.File.IsOptionStrictOn = False AndAlso Helper.CompareType(T, Compiler.TypeCache.System_Object) Then
                    Classification = New LateBoundAccessClassification(Me, m_First, Nothing, Name)
                    Return True
                End If

                Return Compiler.Report.ShowMessage(Messages.VBNC30456, Me.Location, Name, T.FullName) AndAlso result
            End If

            members = member.Members
            Dim withTypeArgs As IdentifierOrKeywordWithTypeArguments
            withTypeArgs = TryCast(m_Second, IdentifierOrKeywordWithTypeArguments)
            If withTypeArgs IsNot Nothing Then
                members = Helper.FilterByTypeArguments(members, withTypeArgs.TypeArguments)
            End If
            members = Helper.FilterExternalInaccessible(Me.Compiler, members)

            If members.Count = 0 Then
                result = Compiler.Report.ShowMessage(Messages.VBNC30456, Me.Location, Name, T.FullName) AndAlso result
                If result = False Then Return result
            End If

            If members.Count > 0 Then
                Dim first As Object = members(0)
                '** If I identifies one or more methods, then the result is a method group with the associated type 
                '   argument list and an associated instance expression of E.
                If Helper.IsMethodDeclaration(first) Then
                    m_First = m_First.GetObjectReference
                    Classification = New MethodGroupClassification(Me, m_First, Nothing, members)
                    Return True
                End If
                '** If I identifies one or more properties, then the result is a property group with an 
                '   associated instance expression of E.
                If Helper.IsPropertyDeclaration(first) Then
                    m_First = m_First.GetObjectReference
                    Classification = New PropertyGroupClassification(Me, m_First, members)
                    Return True
                End If

                If members.Count > 1 Then Throw New InternalException(Me)

                '** If I identifies a shared variable or an instance variable, and if the variable is read-only, 
                '   and the reference occurs outside a constructor of the class in which the variable is declared 
                '   appropriate for the kind of variable (shared or instance), then the result is the value of the 
                '   variable I in the object referenced by E. 
                '   If T is a reference type, then the result is the variable I in the object referenced by E. 
                '   Otherwise, if T is a value type and the expression E is classified as a variable, the result is 
                '   a variable; otherwise the result is a value.
                Dim var As VariableDeclaration = TryCast(first, VariableDeclaration)
                Dim fld As FieldInfo = TryCast(first, FieldInfo)
                If var IsNot Nothing Then
                    Dim constructor As ConstructorDeclaration = Me.FindFirstParent(Of ConstructorDeclaration)()

                    If var.Modifiers.Is(ModifierMasks.ReadOnly) AndAlso (constructor Is Nothing OrElse constructor.Modifiers.Is(ModifierMasks.Shared) <> var.Modifiers.Is(ModifierMasks.Shared)) Then
                        Classification = New ValueClassification(Me, var)
                        Return True
                    ElseIf T.IsClass Then
                        Classification = New VariableClassification(Me, var)
                        Return True
                    ElseIf T.IsValueType Then
                        If m_First.Classification.IsVariableClassification Then
                            Classification = New VariableClassification(Me, var)
                            Return True
                        ElseIf m_First.Classification.IsValueClassification Then
                            Classification = New ValueClassification(Me, var)
                            Return True
                        Else
                            Throw New InternalException(Me)
                        End If
                    Else
                        Throw New InternalException(Me)
                    End If
                ElseIf fld IsNot Nothing Then
                    Dim constructor As ConstructorDeclaration = Me.FindFirstParent(Of ConstructorDeclaration)()
                    If fld.IsInitOnly AndAlso (constructor Is Nothing OrElse constructor.Modifiers.Is(ModifierMasks.Shared) <> fld.IsStatic) Then
                        If fld.IsStatic Then
                            Classification = New ValueClassification(Me, fld, Nothing)
                        Else
                            Classification = New ValueClassification(Me, fld, m_First)
                        End If
                        Return True
                    ElseIf T.IsClass Then
                        If fld.IsStatic Then
                            Classification = New VariableClassification(Me, fld, Nothing)
                        Else
                            Classification = New VariableClassification(Me, fld, m_First)
                        End If
                        Return True
                    ElseIf T.IsValueType Then
                        If m_First.Classification.IsVariableClassification Then
                            If Not TypeOf m_First Is InstanceExpression Then
                                m_First = m_First.GetObjectReference
                            End If
                            If fld.IsStatic Then
                                Classification = New VariableClassification(Me, fld, Nothing)
                            Else
                                Classification = New VariableClassification(Me, fld, m_First)
                            End If
                            Return True
                        ElseIf m_First.Classification.IsValueClassification Then
                            If fld.IsStatic Then
                                Classification = New ValueClassification(Me, fld, Nothing)
                            Else
                                Classification = New ValueClassification(Me, fld, m_First)
                            End If
                            Return True
                        ElseIf m_First.Classification.CanBeValueClassification Then
                            m_First = m_First.ReclassifyToValueExpression
                            result = m_First.ResolveExpression(ResolveInfo.Default(Info.Compiler)) AndAlso result

                            If fld.IsStatic Then
                                Classification = New ValueClassification(Me, fld, Nothing)
                            Else
                                Classification = New ValueClassification(Me, fld, m_First)
                            End If
                            Return True
                        Else
                            Throw New InternalException(Me)
                        End If
                    Else
                        Throw New InternalException(Me)
                    End If
                End If

                '** If I identifies an event, the result is an event access with an associated instance expression of E.
                If Helper.IsEventDeclaration(first) Then
                    Dim red As EventDeclaration = TryCast(first, EventDeclaration)
                    If red Is Nothing AndAlso TypeOf first Is EventDescriptor Then
                        red = DirectCast(first, EventDescriptor).EventDeclaration
                    End If
                    If red IsNot Nothing Then
                        Classification = New EventAccessClassification(Me, red.EventDescriptor, m_First)
                        Return True
                    End If
                    Dim eInfo As EventInfo = TryCast(first, EventInfo)
                    If eInfo IsNot Nothing Then
                        Classification = New EventAccessClassification(Me, eInfo, m_First)
                        Return True
                    End If
                End If

                '** If I identifies a constant, then the result is the value of that constant.
                Dim constant As ConstantDeclaration = TryCast(first, ConstantDeclaration)
                If constant IsNot Nothing Then
                    Classification = New ValueClassification(Me, constant)
                    Return True
                End If

                '** If I identifies an enumeration member, then the result is the value of that enumeration member.
                If Helper.IsEnumFieldDeclaration(first) Then
                    Dim em As EnumMemberDeclaration = TryCast(first, EnumMemberDeclaration)
                    Dim emfld As FieldInfo = TryCast(first, FieldInfo)
                    If em IsNot Nothing Then
                        Classification = New ValueClassification(Me, em)
                        Return True
                    ElseIf emfld IsNot Nothing Then
                        Classification = New ValueClassification(Me, emfld, Nothing)
                        Return True
                    End If
                End If

                '** If T is Object, then the result is a late-bound member lookup classified as a late-bound access 
                '   with an associated instance expression of E.
                If T IsNot Nothing Then
                    Dim td As TypeDescriptor = TryCast(T, TypeDescriptor)
                    Dim compresult As Boolean = False
                    If td Is Nothing Then compresult = Helper.CompareType(T, Compiler.TypeCache.System_Object)
                    If compresult Then
                        Helper.NotImplemented()
                    End If
                End If
                '** Otherwise, E.I is an invalid member reference, and a compile-time error occurs.
                Compiler.Report.ShowMessage(Messages.VBNC30456, Me.Location, Name, T.FullName)
                result = False
            Else
                Compiler.Report.ShowMessage(Messages.VBNC30456, Me.Location, Name, T.FullName)
                result = False
            End If
        End If

        Compiler.Report.ShowMessage(Messages.VBNC30456, Location, Name, m_First.AsString)

        Return False
    End Function

    Shared Function CreateAndParseTo(ByRef result As Expression) As Boolean
        Helper.NotImplemented()
    End Function

    Shared Function IsUnaryMe(ByVal Tm As tm) As Boolean
        Return Tm.CurrentToken.Equals(KS.Dot)
    End Function

    Shared Function IsBinaryMe(ByVal tm As tm) As Boolean
        Return tm.CurrentToken.Equals(KS.Dot)
    End Function

    ReadOnly Property FirstExpression() As Expression
        Get
            Return m_First
        End Get
    End Property

    ReadOnly Property SecondExpression() As IdentifierOrKeyword
        Get
            Return m_Second
        End Get
    End Property

    ReadOnly Property CompleteName() As String
        Get
            Return m_First.ToString & "." & m_Second.Name
        End Get
    End Property

#If DEBUG Then
    Public Overrides Sub Dump(ByVal Dumper As IndentedTextWriter)
        If m_First IsNot Nothing Then m_First.Dump(Dumper)
        Dumper.Write(".")
        Compiler.Dumper.Dump(m_Second)
        'If m_TypeArguments IsNot Nothing Then m_TypeArguments.Dump(Dumper)
    End Sub
#End If
End Class