Class System current status

Bulat Ziganshin bulat.ziganshin at
Fri May 12 12:28:23 EDT 2006

Hello Simon,

Friday, May 12, 2006, 8:05:25 PM, you wrote:

> My suggestion is this:

> * Specify MPTCs in the main language

> * Specify FDs in an Appendix (with some reasonably conservative
>         interpretation of FDs). 

> * A Haskell' implementation should implement the Appendix, and
>         programmers can write programs against it.  But
>         we are advertising specifically that we aren't sure, one way
>         or the other, whether FDs will stay in the language for ever

i agree with that and even feel that this proposal reflect viewpoint of
most of us (of course, i may be wrong). moreover, my own proposal is
essentially the same, only from practical viewpoint - use FDs today
but be ready to reimplement these libs several years later using some
new extension. so the developer will decide whether he prefer to have
maximum features or maximum compatibility

moreover, i think that idea of Appendixes can be used to allow many
other extensions be somewhat standard but not required in each and
every compiler. this includes GADT, concurrency, TH, TRex and many
other things

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at

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