[R6RS] my notes on today's conference call (4 April 2007)

William D Clinger will at ccs.neu.edu
Wed Apr 4 12:02:10 EDT 2007

telephone conference April 4 2007 8:00am-10:00am EDT
Will, Kent, Matthew, Mike present shortly after 8am;
Anton had a serious electrical problem, but joined at 8:14am

0. finalize agenda (1 minute)

1. action items (1 minute)
   - record response votes (All)
   - draft responses for ticket numbers 202, 208, 209, 210, 217, 221, 229
        not done
   - need final resolution in responses for ticket numbers 150, 164
        not done
   - update ticket-nnn responses to reflect decisions:
     184: (Anton) draft kindler, gentler rejection respons
     200: adopt Posix semantics for set-port-position! when underlying
          object is a file
        done, but not decided
     229: strings are not immutable, string-set! in a separate
          library, string-ref preserved, string-ref returns character
          (aka Unicode scalar value), no variable-length strings
          (encourage SRFIs), report should say that string-ref and
          string-set!  should be O(1), add string-for-each
        not done
   - update r6rs to reflect additional decisions:
     - allow (case-lambda)
     - probably use "should" for programmer requirements that implementations
       are not required to enforce

2. allow binary-port port position to be "magic cookie"?
   - ticket 223
        accept formal comment
        decide later whether to allow non-integers

3. add proposed string <=> bytevector conversion routines? (5 minutes)
   - see https://r6rs.scheming.org/node/596
        raise vs replacement semantics
            raise semantics would require more complex spec for recovery
            let's go with replacement semantics
        vote on including these routines with replacement semantics:
            yes: Will, Kent, Matthew, Mike, Anton

4. change the specifications of char-alphabetic?, char-whitespace?, and
   string-titlecase to conform with Unicode? (5 minutes)
   - see http://lists.r6rs.org/pipermail/r6rs-discuss/2007-April/002250.html
        Will so moved; Kent seconded
            yes: Will, Kent, Matthew, Mike, Anton

5. change bytevector port extraction procedure semantics? (5 minutes)
   - ticket 200
   - draft response summary: keep current semantics
        sounds about right
   - is response too detailed?
   - also, should we add file-length?
        doesn't need to be in response to formal comment
    tabled until we have a revised draft response

6. specify freshness/mutability of quasiquoted structure? (5 minutes)
   - ticket 204
        straw poll
            A: Kent, Matthew
            B: Will, Mike
            abstain: Anton
        Kent recommends B because it allows A without requiring
        Mike moved we accept B; Will seconded
            yes: Will, Kent, Matthew, Mike, Anton
        project editor will figure out how to phrase this

7. should <body> allow mixing definitions with expressions? (5 minutes)
   - ticket 212
        Will moved we reject the proposal and explain why; Anton seconded
            (defns and exprs are different, and cannot be made
            interchangeable in all contexts;
            top-levels are messy and icky but pragmatically useful;
            we don't want lambda bodies to be that messy and icky)
            yes: Will, Kent, Matthew, Mike, Anton
        Will will draft response

8. eliminate library export immutability loophole? (5 minutes)
   - ticket 208
   - impact on lambda body?
        adopt the same restriction for lambda bodies?
        should instead of must?
   - impact on top-level body?
        treated as if libraries, so they'd be restricted also
   - impact on letrec and letrec*?
        should (not must?) raise an exception
    tabled until next week
        should there be implicit only-once in library defns?
        same question for internal defns, letrec, letrec*

9. should map return new list structure each time? (5 minutes)
   - ticket 220
   - option 1: entirely new list structure
   - option 2: not modify earlier return values
        Anton moved we require option 2; Will seconded
            yes: Will, Kent, Matthew, Anton
            no: Mike

10. Rename "lookahead" procedure-name prefix to "look-ahead"? (5 minutes)
   - bottom of ticket 214
   - contrast with "bytevector" and "hashtable"
   - rationale: "the unhyphenated form is usually used as a noun"
        Will moved we reject the hyphenated suggestion; Mike seconded
            yes: Will, Matthew, Mike, Anton
            abstain: Kent

11. Remove (r6rs when-unless)? (5 minutes)
   - ticket 211
        Mike moved we remove when and unless from R6RS; Will seconded
            yes: Will, Mike
            no: Kent, Matthew, Anton
   - should we move when and unless into the base library?
        Anton moved when and unless be moved into (r6rs base); Kent seconded
            yes: Kent, Matthew, Anton
            no: Will
            abstain: Mike

12. Make simple conditions more like records? (5 minutes)
   - ticket 210
        tabled until next week
        Mike will draft a response

13. Change exception handling protocol? (5 minutes)
   - ticket 221
        tabled until next week
        Mike will draft a response

14. Replace library form with library prefix? (5 minutes)
   - ticket 150
        Will moved we reject formal comment; Matthew seconded
            yes: Will, Kent, Matthew, Mike, Anton

15. Export bindings for various literals? (10 minutes)
   - ticket 164
   - literals that can appear where non-literals are legitimate:
     - syntax-rules underscore (_), ellipses (...)
     - cond else
     - quasiquote unquote, unquote-splicing
     - quasisyntax unsyntax, unsyntax-splicing
     - others?
   - literals that can appear only where literals are legitimate:
     - case else
     - define-record-type fields, mutable, etc.
     - others?
    Will moved we adopt the last sentence of the formal comment;
        motion failed for lack of a second.
    Matthew dropped out for some technical problem.
    tabled until Matthew could rejoin

16. bytevector aliasing severely impedes optimizations? (5 minutes)
    - ticket 201
        Will will revise the draft response

17. change formal semantics? (5 minutes)
    - tickets 226 (drop library toplevel), 227 (drop define and begin^f)
        Will moved we make the formal semantics non-normative
        and put it in a non-normative appendix; Kent seconded.
            yes: Will, Kent, Mike, Anton
            Matthew was not present for the vote
        the issues for those tickets remain open;
        tabled until next week

adjourned before getting to the next two items:

18. eq? and eqv? should apply to all standardized objects (5 minutes)
    - ticket 155

19. asymmetry between fold-left and fold-right (5 minutes)
    - ticket 170

we meet next week same time, same station

20. adjourned around 10:07am


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