>>>>> "Olin" == shivers  <xxxxxx@ai.mit.edu> writes:

Olin>     From: Tom Lord <xxxxxx@emf.net>
Olin>     * A reasonable alternative is to have two SRFI's: One, a
Olin>       string library without ubiquitous index parameters and
Olin>       without "substring/shared", the other, a SRFI for
Olin>       "substring/shared" in which that procedure is guaranteed to
Olin>       return a value which shares state with its primary string
Olin>       argument.

Olin> SRFI-13 is trying to walk a third path. I'm not willing to *require*
Olin> shared-text substrings. That's just not going to happen out there in
Olin> Scheme-land, at least we can't just mandate it. I'm just trying to allow
Olin> people to write portable code that can run reasonably efficiently across a
Olin> wide range of platforms -- some with shared-text substrings,
Olin> some without.

But efficiency is not the only issue here:  One might want shared-text
substrings for structural reasons.  On the other hand, *optional*
shard-text substrings make for very difficult debugging, especially if
your base implementation does not support them.  That's why I
suggested moving all this stuff out into a separate SRFI and *mandate*
it there.  SRFI 13 as it is simply conflates too many things.

--
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla