Shiro Kawai:
> R6RS #!-switch is the closest I can think of that can make a
> source file self-descriptive about the lexical syntax it uses.
> Did you think about using something like #!c-expr ?

To answer your question, I did think about creating some marker, but I didn't want to clutter the language with a special marker like that.  Earlier versions mandated "(enable-curly-infix)" with the same idea; the advantage of that approach is that it doesn't have to even have cooperation by the reader (as long as there's some way, in that implementation, to override the reader).  It's still there, but merely as a "may".

Instead of cluttering every source file, the draft instead opts to make it an implementation invocation, e.g,. "curly-guile" or whatever.  Then, if you have source code that may use it, you can invoke it to start with.

Of course, that doesn't mean that the current draft is *right* in that aspect :-).

--- David A. Wheeler