Imported from previous forum
[ original email was from Joseph Horowitz - jhorowitz@aegisoft.com ]
Since this working group is tackling the thorny issue of custom tags may I suggest re-reviewing a suggestion I posted ( http://fixprotocol.org/discuss/read/c350a885 ) which was based on an idea that was originally made by Benedict Zoe of Bloomberg ( ttp://www.fixprotocol.org/cgi-bin/BBS.cgi?menu=712&;board=3&message=26&thread=26 )
I think this idea is worth repeating (small pun intended), below:
May I suggest adding a new EndRepeatingGroup tag, to indicate the end of a repeating group. Utilizing such a tag would provide several advantages:
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Eliminate the restriction: “Fields within repeating data groups must be specified in the order that the fields are specified in the message definition within the FIX specification document.” - since it would now be clear where the repeating group ends and the base message, or outer repeating group, continues.
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Eliminate the ambiguity, or error, that can occur in the rare case when the same tag is defined within the middle of a repeating group and within the base message, or outer repeating group.
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Make the use of Custom Tags within a repeating group unambiguous and permissible. As the specification stands today, there is no clear definition where a Custom Tag may be placed within a repeating group. The problem becomes more difficult when parsing the last repeated instance.
Although this change would incur the minimal overhead of one additional tag per repeating group (NoXXX field), I believe this small change would provide greater clarity and flexibility for encoding and parsing repeating groups.
Joey Horowitz
Aegis Software Inc.
P.S. Adding a new (optional) BeginRepeatingGroup tag would also be nice, and allow for the creation of custom repeating groups (this should be considered separately).