Re: 31395511: "Don’t attempt to modify constant strings"

["João Távora" <joaotavora@gmail.com>]

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On Sat, Jun 6, 2020 at 12:41 PM João Távora <joaotavora@gmail.com> wrote:

> On Sat, Jun 6, 2020 at 2:43 AM Paul Eggert <eggert@cs.ucla.edu> wrote:
>
>> On 6/5/20 4:19 PM, João Távora wrote:
>> > I totally agree it is
>> > undefined behaviour to change structure of literals (quoted or
>> > self-evaluating objects), also in Common Lisp, because compilers are
>> > probably allowed to reuse parts of the internal structure of such
>> > objects.  But that's a far cry from having two different manifestations
>> > of `equal` such objects _be_ the same object, but only for compiled
>> > code.
>>
>> I don't understand this remark, as the idea that "compilers are allowed
>> to reuse
>> parts" necessarily implies that (eq "a" "a") can be t if the compiler
>> decides to
>> reuse the string.
>
>
> Depending on the implementation of sequences, it could reuse only the
> later parts of the sequences to maintain uniqueness and still have
>

I forgot to finish the sentence: "and still have some some reuse".

João

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