Composition operator [was: Re: Records in Haskell]

Brandon Allbery allbery.b at
Fri Jan 13 03:09:50 CET 2012

On Thu, Jan 12, 2012 at 19:38, Donn Cave <donn at> wrote:

> >> > Seems obvious to me:  on the one hand, there should be a plain-ASCII
> >> > version of any Unicode symbol; on the other, the ASCII version has
> >> > shortcomings the Unicode one doesn't (namely the existing conflict
> between
> >> > use as composition and use as module and now record qualifier).  So,
> the
> >> > Unicode one requires support but avoids weird parse issues.
> >>
> >> OK.  To me, the first hand is all you need - if there should be a
> >> plain-ASCII version of any Unicode symbol anyway, then you can avoid
> >> some trouble by just recognizing that you don't need Unicode symbols
> >> (let alone with different parsing rules.)
> >>
> >
> > What?  The weird parsing rules are part of the ASCII one; it's what the
> > Unicode is trying to *avoid*. We're just about out of ASCII, weird
> parsing
> > is going to be required at some point.
> What what?  Are you not proposing to allow both ways to write
> composition, "." and "<unicode symbol>" at the same time, but
> with different syntactical requirements?  Unicode characters as
> code would be bad enough, but mixing them with a hodge-podge of
> ASCII aliases with different parsing rules isn't going to win
> any prizes for elegance.

Backward compatibility is rarely elegant, and this is in any case
piggybacking on already existing (indeed, longstanding) parser horkage.
 The point of the Unicode is a first step at getting away from said
horkage, which hopefully can be completed someday.

brandon s allbery                                      allbery.b at
wandering unix systems administrator (available)     (412) 475-9364 vm/sms
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