unaryplusexpression.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 UnaryPlusExpression
    Inherits UnaryExpression

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

    Shadows Sub Init(ByVal Expression As Expression)
        MyBase.Init(Expression)
    End Sub

    Protected Overrides Function GenerateCodeInternal(ByVal Info As EmitInfo) As Boolean
        Dim result As Boolean = True

        ValidateBeforeGenerateCode(Info)

        Dim expInfo As EmitInfo = Info.Clone(True, False, OperandType)
        result = Expression.GenerateCode(expInfo) AndAlso result

        Select Case OperandTypeCode
            Case TypeCode.Decimal
            Case TypeCode.Single, TypeCode.Double
            Case TypeCode.SByte, TypeCode.Int16, TypeCode.Int32, TypeCode.Int64
            Case TypeCode.Byte, TypeCode.UInt16, TypeCode.UInt32, TypeCode.UInt64
            Case TypeCode.Object
                Helper.Assert(Helper.CompareType(OperandType, Compiler.TypeCache.System_Object))
                Emitter.EmitCall(Info, Compiler.TypeCache.MS_VB_CS_Operators__PlusObject_Object)
            Case Else
                Throw New InternalException(Me)
        End Select

        Return result
    End Function

#If DEBUG Then
    Public Overrides Sub Dump(ByVal Dumper As IndentedTextWriter)
        Dumper.Write("+")
        Expression.Dump(Dumper)
    End Sub
#End If

    Public Overrides ReadOnly Property ConstantValue() As Object
        Get
            Helper.Assert(IsConstant)
            Dim value As Object = Expression.ConstantValue
            Return value
        End Get
    End Property

    Public Overrides ReadOnly Property Keyword() As KS
        Get
            Return KS.Add
        End Get
    End Property
End Class