> My suggestions to start :
> 1) define a **simple but significative** domain ,ie "this grammar is for
> subset of ConTeXt language dedicated to variable-data pdf forms"

yes

> 2) make a bnf grammar spec

yes

> 3) build a parser lex/yacc for 2)

later
why ?  There is no difference between 2 and 3

I think a wiki would be a better forum than this mailing-list ?
hmm
"this" mailing-list is ok for this kind of discussions
"a wiki" is wiki.contextgarden.net
and you should put  your results in your personal page


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luigi