[R6RS] modules

[R. Kent Dybvig]

> Ideally we can keep the issue of extending internal definitions
> distinct from the module discussion, which could be done by having
> an internal require that had a body.  As far as I can tell there is
> no semantic difference because requires have no dependence on their
> own lexical environment and so can always be lifted out of the block
> in which they appear.
>   (let ()  ... (require a) ... (require b) ...)
> is equivalent to 
>   (require-with-body (a b) (let () ... ... ...))

Perhaps, but the (require M) form is still more general, since it
allows me to construct derived definitions involving requires and other
definitions.

Kent