guile-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Guile BUG: What's wrong with this?


From: Ludovic Courtès
Subject: Re: Guile BUG: What's wrong with this?
Date: Sat, 07 Jan 2012 23:25:07 +0100
User-agent: Gnus/5.110018 (No Gnus v0.18) Emacs/24.0.90 (gnu/linux)

Hi,

Mark H Weaver <address@hidden> 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 error; scm_nullstr is actually
> used in several files.  However, I looked at each use, and in all cases
> a mutable string is appropriate.  Also, it is SCM_INTERNAL.  So I
> committed the change.

Good!

> However, I wonder if we should also remove this optimization from
> scm_from_stringn, as Bruce suggested.  The R5RS says that `string' and
> `make-string' should return "a newly allocated string", which implies
> that the new string should not be `eq?' to any existing object.
>
> Although our docs for scm_from_stringn et al do not explicitly specify
> that the string is newly allocated, an argument could be made that we
> should follow the behavior of `string'.
>
> What do other people think?

Makes sense to return a new empty string, yes.

Ludo’, who is hoping for the day where strings are immutable, period.  :-)




reply via email to

[Prev in Thread] Current Thread [Next in Thread]