[Scheme-reports] Boolean hemlines Alan Watson (12 Apr 2012 02:30 UTC)
Re: [Scheme-reports] Boolean hemlines John Cowan (12 Apr 2012 04:09 UTC)
Re: [Scheme-reports] Boolean hemlines Peter Bex (12 Apr 2012 07:49 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Queiroz (12 Apr 2012 07:51 UTC)
Re: [Scheme-reports] Boolean hemlines Alaric Snell-Pym (12 Apr 2012 09:22 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Shinn (12 Apr 2012 11:52 UTC)
Re: [Scheme-reports] Boolean hemlines Alan Watson (12 Apr 2012 13:02 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Shinn (12 Apr 2012 13:46 UTC)
Re: [Scheme-reports] Boolean hemlines Jeronimo Pellegrini (12 Apr 2012 13:58 UTC)
Re: [Scheme-reports] Boolean hemlines Alan Watson (12 Apr 2012 16:08 UTC)
Re: [Scheme-reports] Boolean hemlines Marc Feeley (12 Apr 2012 13:09 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Shinn (15 Apr 2012 14:32 UTC)
Re: [Scheme-reports] Boolean hemlines John Cowan (12 Apr 2012 13:57 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Shinn (14 Apr 2012 01:58 UTC)
Re: [Scheme-reports] Boolean hemlines John Cowan (14 Apr 2012 02:41 UTC)
Re: [Scheme-reports] Boolean hemlines Alex Shinn (14 Apr 2012 03:00 UTC)
Re: [Scheme-reports] Boolean hemlines John Cowan (14 Apr 2012 03:08 UTC)

Re: [Scheme-reports] Boolean hemlines Alan Watson 12 Apr 2012 13:01 UTC

> On Thu, Apr 12, 2012 at 11:29 AM, Alan Watson <alan@alan-watson.org> wrote:
>> A long time ago, some people made the decision that #t/#f were in some sense better than #!true/#!false. More recently, the WG1 have made a different decision that #true/#false are in some sense better than #t/#f.
>>
>> This decision is not without cost. If an R7RS Scheme writes a boolean datum as #true or #false, it likely cannot be read by a R4RS, R5RS, or R6RS Scheme. It is unrealistic and probably undesirable to require perfect compatibility between iterations of Scheme, but changing the spelling a fundamental data is perhaps unexpected. The WG1 needs to decide if this cost is acceptable, and if not either revert their decision to allow #true/#false or require write to produce #t/#f.
>
> Thank you for the feedback.  However, before you jump to the conclusion that
> we threw this in frivolously, or that the WG members voted without thinking
> at all about the consequences, perhaps you could ask for our rationale?

Hang on a second. I didn't say or imply that this was frivolous and I did not say or imply that you did this without thinking about the consequences. I just pointed out a cost and said you needed to consider it. Furthermore, one of my suggestions for mitigating the cost (having write produce #t/#f) explicitly left the new spellings intact.

I did look for the rationale, but did not find any discussion of the implications for sharing data between different generations of Scheme. Perhaps I missed it, and if so I apologize for wasting your time.

Regards,

Alan

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