public static FTL.AST.INode Parse(CharStream cs)
{
FTL.AST.INode expression = Expresson.Parse(cs);
int bufferPos = cs.Position;
WhiteSpace.Parse(cs);
if (cs.PeekNext() != SEPERATOR[0])
{
// it's not a select expression, so let's return early
cs.Rewind(bufferPos);
return(expression);
}
// it must be a select expression
cs.SkipString(SEPERATOR);
WhiteSpace.Parse(cs);
// we expect now a memberList (REQUIRED)
FTL.AST.MemberList memberList = MemberList.Parse(cs);
// skip extra new-line in case one is available
if (CharStream.IsNL(cs.PeekNext()))
{
NewLine.Parse(cs);
}
// return it all
return(new FTL.AST.SelectExpression(expression, memberList));
}
private void checkValidExpression <T>(string input, string rest = "")
{
var cs = NCS(input);
var expression = Expresson.Parse(cs);
Assert.IsNotNull(expression);
Assert.AreEqual(rest, cs.ReadUntilEnd());
Assert.AreEqual(typeof(T), expression.GetType());
}