You have the right idea.  Unfortunately, I do not get to dictate the syntax 
of this file I get to parse and there is considerable ambiguity in 
comments.  There are essentially three forms of a comment.  Two forms of 
this comment include information I need to parse.  One form 
(non-information comment) does not contain useful information.  

1) embedded base number --> Matches OptEmbeddedBase --> Actual information 
I need.  Discernable from a non-information comment by it's location 
immediately after the opening of a pattern list brace and that if must 
contain '#base=<list>', where <list> is a comma delimited list of integers.

2) tag string --> Matches TagStr --> Again, information I need.  
Discernable from a non-information comment by location after a pattern 
declaration and by the fact that it is bookended by '#' symbols can can 
only contain a comma delimited list of word (\w) characters.  Technically, 
whitespace is not allowed inside these strings either.  I figured I'd sort 
that out once I had it matching as is.

3) Non information comment -> Matches COMMENT --> Can be discarded.  This 
is any comment that does not match one of the first two forms.

Hopefully that's helpful.  When you say that you'd 'simply say that in the 
grammar', I'm confused.  Is this not what I'm saying in the grammar in the 
TagStr rule by setting '#' characters before and after the TagList rule?  
Is there a better way to resolve this ambiguity?

On Friday, May 9, 2014 11:46:16 AM UTC-7, Jeffrey Kegler wrote:
>
> Trying to get the idea, is it that tags use '#' as a delimiter, much in 
> the same way that strings use quotes?  And that's it's a comment if 
> there's a '#' that is not matched before the newline?  That is, that in 
>
>      Pat n2000000g0000002; #HOT# # Not so hot 
>
> "#HOT#" is a tag, and "# Not so hot" is a comment? 
>
> If that's the case, I'd simply say that in the grammar.  I'd give more 
> detail, but I'm not 100% clear on the intent at this point. 
>
> -- jeffrey 
>

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