[wg-camlp4] My uses of syntax extension

[Leo White]

>> I second Leo's idea to leave it to the preprocessor.
>
>I would strongly argue for a convention that has to be obeyed by all 
>preprocessors. If you leave it to the preprocessor, you will have to 
>call the preprocessor during the parsing, not during the typing, i.e. 
>you won't have access to the typing environment while expanding macros. 
>Consequently, your objectives were to be strictly more powerful, but 
>your system would actually be strictly less powerful.

There is no reson that you cannot expand the preprocessor during typing. As 
I said in a previous post, all we need to provide is a function that will 
parse an expression upto the next unnested occurence of "$" or whatever the 
preprocessor is using to mark the end of its antiquotations. Preprocessors 
can then simply use this facility to handle their antiquotations 
themselves.