private OperatorExpressionNode RelationalOperation(string expression)
{
OperatorExpressionNode node = null;
if (Same(expression, Token.TokenType.LessThan))
{
node = new LessThanExpressionNode();
}
else if (Same(expression, Token.TokenType.GreaterThan))
{
node = new GreaterThanExpressionNode();
}
else if (Same(expression, Token.TokenType.LessThanOrEqualTo))
{
node = new LessThanOrEqualExpressionNode();
}
else if (Same(expression, Token.TokenType.GreaterThanOrEqualTo))
{
node = new GreaterThanOrEqualExpressionNode();
}
else if (Same(expression, Token.TokenType.EqualTo))
{
node = new EqualExpressionNode();
}
else if (Same(expression, Token.TokenType.NotEqualTo))
{
node = new NotEqualExpressionNode();
}
return(node);
}
private GenericExpressionNode RelationalExpr(string expression)
{
{
GenericExpressionNode lhs = Factor(expression);
if (null == lhs)
{
this.errorPosition = this._lexer.GetErrorPosition();
}
OperatorExpressionNode node = RelationalOperation(expression);
if (node == null)
{
return(lhs);
}
GenericExpressionNode rhs = Factor(expression);
node.LeftChild = lhs;
node.RightChild = rhs;
return(node);
}
}