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Re: [Scheme-reports] quasiquote and cycles

On Tue, Jul 5, 2011 at 7:57 AM, Per Bothner <per@x> wrote:
> Well, if R7RS has quasiquote and self-referential literals, then in the
> spirit
> of Scheme they should work well together, without "needless restrictions".
> But at least the standard should specify what a programmer can expect to
> have work.

In the draft 1, <qq-template> only allows <simple datum> in it (as opposed
to <datum>), which excludes #n= and #n#.  So I understand that
`#0=(,foo #0#) is outside of the current draft and the outcome would be
unspecified implicitly.

However, I find it interesting to allow self-referential structure with
quasiquotation, so if you're proposing such enhancement I don't
object.  If you do, certainly the standard will need to say how it should

(BTW, I think in the draft 1 pdf, section 7.1.2, the rule

  <datum> -> .... | <label> <datum> | ...

should be

  <datum> -> ... | <label> = <datum> | ...

in case if this hasn't been addressed.)

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