[r6rs-discuss] [Formal] String positions and string slices

From: Joe Marshall <jmarshall>
Date: Tue, 10 Apr 2007 12:51:39 -0700

On 4/10/07, Marcin 'Qrczak' Kowalczyk <qrczak at knm.org.pl> wrote:
> Dnia 09-04-2007, pon o godzinie 19:12 -0400, William D Clinger
> napisa?(a):
>
> > (text-position=? position1 position2)
> >
> > True iff both positions identify the same positions within
> > the same text. Should run in O(1) time.
>
> If text is immutable, then the concept of "same text" is unclear:
>
> ? If it means eqv?, then achieving O(1) is impractical.
>
> ? If it means eq?, then it distinguishes cases for which there is
> no practical reason to distinguish them (when distinct text objects
> contain equivalent text).

If text is immutable, it may be interned.

-- 
~jrm
Received on Tue Apr 10 2007 - 15:51:39 UTC

This archive was generated by hypermail 2.3.0 : Wed Oct 23 2024 - 09:15:01 UTC