cobjexpression.vb

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' 
' Visual Basic.Net Compiler
' Copyright (C) 2004 - 2007 Rolf Bjarne Kvinge, [e-mail]
' 
' This library is free software; you can redistribute it and/or
' modify it under the terms of the GNU Lesser General Public
' License as published by the Free Software Foundation; either
' version 2.1 of the License, or (at your option) any later version.
' 
' This library is distributed in the hope that it will be useful,
' but WITHOUT ANY WARRANTY; without even the implied warranty of
' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
' Lesser General Public License for more details.
' 
' You should have received a copy of the GNU Lesser General Public
' License along with this library; if not, write to the Free Software
' Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
' 

Public Class CObjExpression
    Inherits ConversionExpression

    Sub New(ByVal Parent As ParsedObject, ByVal Expression As Expression)
        MyBase.New(Parent, Expression)
    End Sub

    Sub New(ByVal Parent As ParsedObject)
        MyBase.New(Parent)
    End Sub

    Protected Overrides Function ResolveExpressionInternal(ByVal Info As ResolveInfo) As Boolean
        Dim result As Boolean = True

        result = MyBase.ResolveExpressionInternal(Info) AndAlso result
        result = Validate(Info, Expression.ExpressionType) AndAlso result

        Return result
    End Function

    Shared Function Validate(ByVal Info As ResolveInfo, ByVal SourceType As Type) As Boolean
        Dim result As Boolean = True

        'Dim expType As Type = SourceType
        'Dim expTypeCode As TypeCode = Helper.GetTypeCode(Compiler, expType)
        'Dim ExpressionType As Type = Info.Compiler.TypeCache.ULong

        Return result
    End Function

    Overloads Shared Function GenerateCode(ByVal Expression As Expression, ByVal Info As EmitInfo) As Boolean
        Dim result As Boolean = True

        If Info.IsRHS Then
            result = Expression.GenerateCode(Info.Clone(True, False, Expression.ExpressionType)) AndAlso result
            If Expression.ExpressionType.IsValueType OrElse Expression.ExpressionType.IsGenericParameter Then
                Emitter.EmitBox(Info, Expression.ExpressionType)
            End If
        Else
            Throw New InternalException(Expression)
        End If

        Return result
    End Function

    Protected Overrides Function GenerateCodeInternal(ByVal Info As EmitInfo) As Boolean
        Return GenerateCode(Me.Expression, Info)
    End Function

    Public Overrides ReadOnly Property IsConstant() As Boolean
        Get
            Return False
        End Get
    End Property

    Overrides ReadOnly Property ExpressionType() As Type
        Get
            Return Compiler.TypeCache.System_Object
        End Get
    End Property
End Class