Am So., 22. Sept. 2024 um 12:08 Uhr schrieb Daphne Preston-Kendal < d...@nonceword.org>:
> On 18 Sep 2024, at 17:25, Marc Nieper-Wißkirchen <marc.nie...@gmail.com> > wrote: > > > And the text reflects this by saying that the keys should have > locations. This means that you won't see a catastrophic failure, but you > have to know what you do (and your implementation of SRFI 254). > > > >> I think it is probably a bad idea, because what has location and what > >> does not is implementation-dependent – beyond matters which, in R6 and > > > > It is partially implementation-dependent, which is an important > distinction. The RnRS define a lot of value types that have locations. > > In order words, it is implementation-dependent. > Sure, but that misses the point. > Writing portable code that uses SRFI 254 will be a nightmare I don't believe so. > if it is not possible to pass any given object into an ephemeron or > guardian. > Why would you ever want to pass *any* object into an ephemeron or guardian? > I would maybe accept a restriction on passing some very minimal set of > types as keys to an ephemeron: #t, #f, '(). > Anything else might have location in a given implementation. > (We mustn’t forget that R7-small implementations with no fixnums, i.e. > where all numbers are boxed like in CPython, may also want to support SRFI > 254.) > > > Daphne > >
