/*
* statementSequence = statement { statement }.
*/
SyntaxTreeNode IsStatementSequence()
{
SyntaxTreeSequenceNode statementSequenceNode = null;
SyntaxTreeNode statementNode;
FilePosition position = GetInputFilePosition();
if (null != (statementNode = IsStatement()))
{
statementSequenceNode = new SyntaxTreeSequenceNode(position, statementNode, statementSequenceNode);
statementSequenceNode.AppendToLast();
}
SyntaxTreeNode firstStatementNode = statementSequenceNode;
while (null != (statementNode = IsStatement()))
{
position = GetInputFilePosition();
statementSequenceNode = new SyntaxTreeSequenceNode(position, statementNode, statementSequenceNode);
statementSequenceNode.AppendToLast();
}
return firstStatementNode;
}
/*
* declaration = typeName identifier { COMMA_SYMBOL identifier }.
*/
SyntaxTreeNode IsDeclaration()
{
bool commaOccurred = false;
SyntaxTreeNode firstDeclSequeceNode = null;
SyntaxTreeSequenceNode declSequenceNode = null;
SyntaxTreeNode declNode = null;
SyntaxTreeNode typeNode;
FilePosition position = GetInputFilePosition();
if (null != (typeNode = IsTypeName()))
{
do
{
Symbol currentSymbol = this._scanner.PeekSymbol();
if (this._symbolTable.IsIdentifierSymbol(currentSymbol))
{
declNode = new SyntaxTreeDeclarationNode(position, typeNode, currentSymbol);
this._symbolTable.SetDeclarationNodeLinkToSymbol(currentSymbol, declNode);
this._scanner.NextSymbol();
if (this._scanner.PeekSymbol() == Symbol.EOF)
{
return CreateErrorNode("Unexpected EOF", false);
}
}
else
{
return CreateErrorNode("Identifier expected after type name");
}
if (this._scanner.PeekSymbol() == Symbol.COMMA_SYMBOL)
{
position = GetInputFilePosition();
declSequenceNode = new SyntaxTreeSequenceNode(position, declNode, declSequenceNode);
declSequenceNode.AppendToLast();
if (!commaOccurred)
{
commaOccurred = true;
firstDeclSequeceNode = declSequenceNode;
}
this._scanner.NextSymbol();
if (this._scanner.PeekSymbol() == Symbol.EOF)
{
return CreateErrorNode("Unexpected EOF", false);
}
}
else if (this._scanner.PeekSymbol() == Symbol.DELIMITER_SYMBOL)
{
position = GetInputFilePosition();
declSequenceNode = new SyntaxTreeSequenceNode(position, declNode, declSequenceNode);
declSequenceNode.AppendToLast();
if (!commaOccurred)
{
firstDeclSequeceNode = declSequenceNode;
}
}
else
{
return CreateErrorNode("\',\' or \';\' expected after an identifier in a declaration");
}
} while (Symbol.DELIMITER_SYMBOL != this._scanner.PeekSymbol());
}
return firstDeclSequeceNode;
}
