private void OnRunButtonClick(object sender, RoutedEventArgs e)
{
// Create the lexer and parser
Lexer lexer = new Lexer(QueryText.Text);
Parser parser = new Parser(lexer);
// Get the root of the AST and evaluate the query, printing the results
Expr rootExpr = parser.GetExpression();
if (rootExpr == null)
{
ResultsText.Text = "Error: No expression produced";
}
else
{
Result result = rootExpr.Evaluate();
if (result.ValueType == ResultValueType.String)
{
ResultsText.Text = result.StringValue;
}
else if (result.ValueType == ResultValueType.Int)
{
ResultsText.Text = "Int value: " + result.IntValue.ToString();
}
else if (result.ValueType == ResultValueType.Rows)
{
StringBuilder builder = new StringBuilder();
int index = 0;
foreach (ResultRow row in result.RowsValue)
{
builder.Append(index++);
foreach (string field in row)
{
builder.Append(" | ");
builder.Append(field);
}
builder.AppendLine();
}
ResultsText.Text = builder.ToString();
}
}
}
private void OnLexButtonClick(object sender, RoutedEventArgs e)
{
Lexer lexer = new Lexer(QueryText.Text);
while (true)
{
Token token = lexer.Next();
if (token.Type == TokenType.EndOfFile)
{
break;
}
else if (token.Type == TokenType.Error)
{
Console.WriteLine("Error in {0}", token.Value);
break;
}
else
{
Console.WriteLine("token: {0} (value: '{1}')", token.Type.ToString(), token.Value);
}
}
}
public Parser(Lexer lexer)
{
mLexer = lexer;
}