>> m4...doesn't assume anything about the underlying text. I don't think there is anything wrong for the meta layer (syntax layer) to make certain assumptions/

>> m4...doesn't assume anything about the underlying text. I don't think there is anything wrong for the meta layer (syntax layer) to make certain assumptions/restriction for the underlying language layer; and there is nothing wrong for the meta layer to reflect certain characteristics of the underlying languages. The argument is: syntax matters, but it is not necessary to judge (or even reject) a language by its syntax, which may be remedied by a meta layer. It is not necessary to reject a person by his clothes or even how he talks. The same should go to a programming language.