[This message was posted by David Rosenborg of Pantor Engineering AB <[email protected]> to the "FAST Protocol" discussion forum at http://fixprotocol.org/discuss/46. You can reply to it on-line at http://fixprotocol.org/discuss/read/7828fd96 - PLEASE DO NOT REPLY BY MAIL.]
How an empty string is represented within a particular implementation is not specified by the FAST specification. However, it should of course have the length 0. If the subtraction length is 1 and the base value is the empty string, then this is indeed an error. When you get the subtraction length 1, is this after you've adjusted it for the excess-1 coding used for nullable string deltas? Otherwise that could explain the problem you're facing. /David > Hi, I'm trying to decode the SWX FAST stream, and in particular an > optional ASCII string attribute (named RandomisedInterval) with delta > operator and no initial value (default base value 'Empty String' is > used). Let suppose we have an undefined dictionary previous value (i.e. > the 'Empty String' should be used as previous value) and we read from > the stream an ASCII String Delta made by a Substraction Length = 1 > followed by an ASCII String that in that case corresponds to the whole > RandomisedInterval string "00:02:00". > > The problem I'm facing with is quite simple: since I consider the 'Empty > String' (the default base value) as a string with lenght=0, a > Substraction Length = 1 (meaning to remove 1 character from the back of > base value) makes my application to report the error [ERR D7]. > > I would like to undertand if I'm making a mistake calculating the actual > length of the 'Empty String' or if the right behaviour is actually to > report the error. > > > Furthermore, since I also consider the string "\0" as it had length=0, I > think a similar problem could arise in any case I have a dictionary > previous value = 'Empty String' or "\0". > > Many thanks in advance. [You can unsubscribe from this discussion group by sending a message to mailto:[email protected]] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Financial Information eXchange" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/FIX-Protocol?hl=en -~----------~----~----~----~------~----~------~--~---
