Arpad-The editorial change you suggest looks good to me. I think the KISS principle applies here.
Thanks. Mike Steinberger On 03/07/2012 01:37 PM, Muranyi, Arpad wrote:
Hello, This is mainly a question for the authors of the original IBIS-AMI specification about the syntax of "Format List". The editorial committee is trying to figure out the original intent of the syntax of List. The question is regarding the first item in the list called "<typ value>". This is what I see on page 140: | Format: (default is range) | Value <value> Single value data | Range <typ value> <min value> <max value> | List <typ value> <value> <value> <value> ... <value> and there seems to be at least two interpretations for "<typ value>". One interpretation would treat all entries in the list as "THE list", like this: (List 1 2 3 4 5 6 7 8 9) \----------------/ this entire thing being the "list" The other interpretation would take the first number as an indicator for which value in the list should be used if Default doesn't exist and the user doesn't make a selection: (List 5 1 2 3 4 5 6 7 8 9) | \----------------/ | this thing being | the "list" | \ this value might be a repeated entry from the "list that follows" to indicate which value in the list is to be considered if Default is not defined or the user doesn't make a selection In the absence of Default, both of these interpretations would pick the "first item", but note that in the second interpretation that first item is repeated in the body of the list. In order to achieve the same outcome as in the second example without the repetition, one could provide a list using a different order: (List 5 1 2 3 4 6 7 8 9) \----------------/ this entire thing being the "list" but visually this is not as appealing or readable. There are probably many other detail questions and comments about this, but I would like to get an answer first on what the authors had in mind when this was written. My take on this is that what the spec calls the "<typ value>" was really intended to be the "<default value>". The problem is that the word "typ" has a completely different meaning in the IBIS context and mixing those meanings into the interpretation of Format List ends up with different expectations and assumptions. I would suggest to replace | List <typ value> <value> <value> <value> ... <value> with: | List <default value> <value> <value> <value> ... <value> as an editorial change and be done. A related, but different question is whether we allow repeated entries in the list. To me it doesn't make any sense, but the spec doesn't say so. Should that be allowed, or prohibited? Yet another question: Is a list supposed to have more than one values, or can it also have one value? If so, what is the difference between Format List, or Format Value? I would prefer to keep the solution to these questions simple, so we could resolve this as an editorial change without having to write another BIRD... Thanks, Arpad =========================================================