parser(expressions).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
' 


Partial Class Parser

    Private Function ParseGlobalExpression(ByVal Parent As ParsedObject) As GlobalExpression
        tm.AcceptIfNotInternalError(KS.Global)
        Return New GlobalExpression(Parent)
    End Function

    Private Function ParseBuiltInTypeExpression(ByVal Parent As ParsedObject) As BuiltInTypeExpression
        Dim result As New BuiltInTypeExpression(Parent)

        Dim m_Type As BuiltInDataTypes

        Helper.Assert(tm.CurrentToken.Equals(Enums.BuiltInTypeTypeNames))

        m_Type = CType(tm.CurrentToken.Keyword, BuiltInDataTypes)
        tm.NextToken()

        result.Init(m_Type)

        Return result
    End Function

    ''' <summary>
    ''' MemberAccessExpression ::= [ [ MemberAccessBase ] "." ] IdentifierOrKeyword
    ''' MemberAccessBase ::= Expression | BuiltInTypeName | "Global" | "MyClass" | "MyBase"
    ''' 
    ''' TODO: Is this correct? Is the "." optional in a MemberAccessExpression?
    ''' LAMESPEC: IdentifierOrKeyword should be followed by type parameters...
    ''' MemberAccessExpression ::= [ [ MemberAccessBase ] "." ] IdentifierOrKeyword [ TypeParametersList ]
    ''' </summary>
    ''' <param name="FirstExpression"></param>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Private Function ParseMemberAccessExpression(ByVal Parent As ParsedObject, ByVal FirstExpression As Expression) As MemberAccessExpression
        Dim result As New MemberAccessExpression(Parent)

        Dim m_First As Expression
        Dim m_Second As IdentifierOrKeywordWithTypeArguments

        m_First = FirstExpression 'Might be nothing.
        If m_First IsNot Nothing Then m_First.Parent = result
        'According to the language specification, the dot is optional,
        'but that doesn't seem to be correct... so let's make it 
        'required
        tm.AcceptIfNotInternalError(KS.Dot)
        'Specifically, this is not a MemberAccessExpression without the
        'dot, so it is an internal error.

        m_Second = ParseIdentifierOrKeywordWithTypeArguments(result)
        If m_Second Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_First, m_Second)

        Return result
    End Function

    Private Function ParseIdentifierOrKeywordWithTypeArguments(ByVal Parent As ParsedObject) As IdentifierOrKeywordWithTypeArguments
        Dim result As New IdentifierOrKeywordWithTypeArguments(Parent)

        Dim m_TypeArguments As TypeArgumentList
        Dim m_Token As Token

        If tm.CurrentToken.IsIdentifierOrKeyword Then
            m_Token = tm.CurrentToken
            tm.NextToken()
        Else
            Helper.ErrorRecoveryNotImplemented()
            Return Nothing
        End If

        If tm.CurrentToken.Equals(KS.LParenthesis) AndAlso tm.PeekToken.Equals(KS.Of) Then
            m_TypeArguments = ParseTypeArgumentList(result)
            If m_TypeArguments Is Nothing Then Helper.ErrorRecoveryNotImplemented()
        Else
            m_TypeArguments = Nothing
        End If

        result.Init(m_Token, m_TypeArguments)

        Return result
    End Function

    ''' <summary>
    ''' DictionaryAccessExpression ::= [Expression] "!" IdentifierOrKeyword
    ''' </summary>
    ''' <remarks></remarks>
    Private Function ParseDictionaryAccessExpression(ByVal Parent As ParsedObject, ByVal FirstPart As Expression) As DictionaryAccessExpression
        Dim result As New DictionaryAccessExpression(Parent)

        Dim m_FirstPart As Expression
        Dim m_SecondPart As IdentifierOrKeyword

        m_FirstPart = FirstPart
        If m_FirstPart IsNot Nothing Then m_FirstPart.Parent = result
        tm.AcceptIfNotInternalError(KS.Exclamation)
        If tm.CurrentToken.IsIdentifierOrKeyword Then
            m_SecondPart = ParseIdentifierOrKeyword(result)
            If m_SecondPart Is Nothing Then Helper.ErrorRecoveryNotImplemented()
        Else
            Compiler.Report.ShowMessage(Messages.VBNC30203)
            Return Nothing
        End If

        result.Init(m_FirstPart, m_SecondPart)

        Return result
    End Function

    Private Function ParseCByteExpression(ByVal Parent As ParsedObject) As CByteExpression
        Dim result As New CByteExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CByte)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()
        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCBoolExpression(ByVal Parent As ParsedObject) As CBoolExpression
        Dim result As New CBoolExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CBool)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCCharExpression(ByVal Parent As ParsedObject) As CCharExpression
        Dim result As New CCharExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CChar)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCDateExpression(ByVal Parent As ParsedObject) As CDateExpression
        Dim result As New CDateExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CDate)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCDblExpression(ByVal Parent As ParsedObject) As CDblExpression
        Dim result As New CDblExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CDbl)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCDecExpression(ByVal Parent As ParsedObject) As CDecExpression
        Dim result As New CDecExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CDec)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCIntExpression(ByVal Parent As ParsedObject) As CIntExpression
        Dim result As New CIntExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CInt)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCLngExpression(ByVal Parent As ParsedObject) As CLngExpression
        Dim result As New CLngExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CLng)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCObjExpression(ByVal Parent As ParsedObject) As CObjExpression
        Dim result As New CObjExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CObj)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCSByteExpression(ByVal Parent As ParsedObject) As CSByteExpression
        Dim result As New CSByteExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CSByte)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCShortExpression(ByVal Parent As ParsedObject) As CShortExpression
        Dim result As New CShortExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CShort)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCSngExpression(ByVal Parent As ParsedObject) As CSngExpression
        Dim result As New CSngExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CSng)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result
    End Function

    Private Function ParseCStrExpression(ByVal Parent As ParsedObject) As CStrExpression
        Dim result As New CStrExpression(Parent)

        Dim m_Expression As Expression

        tm.AcceptIfNotInternalError(KS.CStr)

        m_Expression = ParseParenthesizedExpression(Parent)
        If m_Expression Is Nothing Then Helper.ErrorRecoveryNotImplemented()

        result.Init(m_Expression)

        Return result