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Re: nested comments (please correct lexical scope)

This page is part of the web mail archives of SRFI 62 from before July 7th, 2015. The new archives for SRFI 62 contain all messages, not just those from before July 7th, 2015.

> Sorry, I mashed three ideas together there:
> 1. I don't think it's a good idea for (#;#;a b c) => (c).

- fully agree, obviously :)

> 2. I would prefer (#;#;a b c) => (b c), analogous to (''a b c).

- as above, implying to me something along the line of:
  (#;#;a b c) :: ({remove {remove a}} b c) => (b c).

> 3. I don't like the suggestion that (#; a) => (a) because of the space.

- only suggested it as although many scheme readers seem to accept:

  '<ws><s-exp> :: {quote a} => (quote <s-exp>)

  r5rs seems to imply in all examples, no <white-space> being allowed
  between the quote abbreviation and it's target <s-exp>; which makes
  sense to me as it visually and lexically binds the reader action with
  it's target <s-exp>, as opposed to allowing something like:

  (+ a b '; some comment
     (- c d))  :: (+ a b {quote (- c d)}) => (+ a b (quote (- c d)))

  or analogously:

  (+ a b #;; some comment
     (- c d))  :: (+ a b {remove (- c d)}) => (+ a b)

  as opposed to requiring no <ws>:

  (+ a b #;; some comment
     (- c d)) :: (+ a b {remove } (- c d)) => (+ a b (- c d))


  (+ a b ; some comment
     #;(- c d)) :: (+ a b {remove (- c d)}) => (+ a b)

  which overall seems like a good thing to enforce?

> To defend my #1: While I understand the "comment out next sexp"
> explanation, my mind sees "A" as the next sexp for /both/ comment tokens
> in (#;#;a b c), thus making it equivalent to (#;a b c) => (b c).