[r6rs-discuss] Unicode issues

From: Jason Orendorff <jason.orendorff>
Date: Wed, 29 Aug 2007 13:58:39 -0400

William D Clinger wrote:
> For interpreters, various segmented representations
> provide O(1) amortized time for both, while avoiding
> the all-or-nothing space dichotomy of the record2
> and record1 representations.
>
> Those are examples of the variable-width representations
> that I would recommend to implementors of Scheme. This
> isn't rocket science; it's just data structures.

The page you linked earlier proposes 7 different string
representations. They have radically different best-case,
expected-case, and worst-case performance. End users are left with no
idea what to expect. R6RS strings are a grimacing caricature of an
abstraction.

It would be all right if more of the proposals were straw men, but in
fact R6RS gives implementors really good reasons to go in at least two
totally different directions: UTF-16 so they can use ICU and
interoperate efficiently with other existing libraries; record2 or
flat4 to conform with the report's recommendation on string-ref and
thus support portable R6RS code that munges strings.

In the quoted bit above, you act as though string-ref and string-set!
are the only pieces of the puzzle. I think they're the easy pieces.

-j
Received on Wed Aug 29 2007 - 13:58:39 UTC