Re: The empty string and other empty strings

2012-01-20 Thread Andy Wingo
On Fri 13 Jan 2012 17:39, Mark H Weaver m...@netris.org writes: Should we defend the legitimacy of this optimization, and ask the R7RS working group to include explicit language specifying that empty strings/vectors need not be freshly allocated? It's a worthwhile question IMO. I'll mail

Re: The empty string and other empty strings

2012-01-16 Thread Marijn
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 13-01-12 17:39, Mark H Weaver wrote: David Kastrup d...@gnu.org writes: However, my mind is not set in stone on this. Does anyone else here agree with David? Should we defend the legitimacy of this optimization, and ask the R7RS working

Re: The empty string and other empty strings

2012-01-16 Thread David Kastrup
Marijn hk...@gentoo.org writes: On 13-01-12 17:39, Mark H Weaver wrote: David Kastrup d...@gnu.org writes: However, my mind is not set in stone on this. Does anyone else here agree with David? Should we defend the legitimacy of this optimization, and ask the R7RS working group to include

Re: The empty string and other empty strings

2012-01-12 Thread Ludovic Courtès
Hi Mark, Mark H Weaver m...@netris.org skribis: What do other people think? As you said, R5RS makes it clear that there can be several (in the sense of eq?) empty strings, so I think what you did is the right thing. Thanks! Ludo’.

The empty string and other empty strings

2012-01-10 Thread Ludovic Courtès
Hello Mark! Mark H Weaver m...@netris.org skribis: I wrote: 3. Make scm_nullstr into a mutable string. After all, it can't be changed anyway, and the _only_ reference to it is from scm_from_stringn, so the result should always be mutable. For the record: my statement above was in

Re: The empty string and other empty strings

2012-01-10 Thread David Kastrup
objects can make this string different from what it is. And since there is no way to share the empty contents of an empty string with other strings, this is true even if every empty string is eq? to every other one. -- David Kastrup