Gary, > Org-mode macros that got expanded in the middle of babel source block > text would be cool. Just saying.
i agree with Eric's comment. if you think of the issue of trying to parse an arbitrary (and growing) number of languages, trying to avoid language-specific constructions in your choice of macro-designator (things like "@@..@@" or "{{..}}" or "$.." or...), etc., you will probably fairly quickly come to see the benefits of :var as the way of passing in inputs. cheers, Greg