public override void Execute()
{
try
{
CommandContext.LastCommandFailed = false;
Scanner scanner = new Scanner();
Parser parser = new Parser(scanner);
ParseTree parseTree = parser.Parse(Statement);
if (0 < parseTree.Errors.Count)
{
throw new ArgumentException(parseTree.Errors[0].Message);
}
object result = parseTree.Eval(null);
ICommand command = (ICommand) result;
CommandContext.ResultWriter = GetResultWriter();
CommandContext.TextWriter = Console.Out;
command.Validate();
command.Execute();
}
catch (Exception ex)
{
CommandContext.LastCommandFailed = true;
if (CommandContext.DebugLog)
{
Console.WriteLine("Command execution failed with error:\n{0}", ex);
}
else
{
while (null != ex.InnerException)
{
ex = ex.InnerException;
}
Console.WriteLine("Command execution failed with error '{0}'", ex.Message);
}
}
}
public Parser(Scanner scanner)
{
this.scanner = scanner;
}