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Re: Escape via unhygienic macros Phil Hofer (04 Jul 2019 17:42 UTC)
Escape via unhygienic macros Phil Hofer (03 Jul 2019 22:59 UTC)
Re: Escape via unhygienic macros John Cowan (04 Jul 2019 03:59 UTC)
Re: Escape via unhygienic macros Marc Nieper-Wißkirchen (04 Jul 2019 05:57 UTC)
Re: Escape via unhygienic macros John Cowan (04 Jul 2019 17:03 UTC)
Re: Escape via unhygienic macros
Re: Escape via unhygienic macros John Cowan (04 Jul 2019 18:55 UTC)
(missing)
Fwd: Escape via unhygienic macros Marc Nieper-Wißkirchen (08 Jul 2019 12:20 UTC)
Re: Escape via unhygienic macros Marc Nieper-Wißkirchen (08 Jul 2019 12:37 UTC)
Re: Escape via unhygienic macros John Cowan (08 Jul 2019 16:27 UTC)
Re: Escape via unhygienic macros Lassi Kortela (04 Jul 2019 19:45 UTC)
Re: Escape via unhygienic macros Lassi Kortela (04 Jul 2019 19:56 UTC)
Re: Escape via unhygienic macros John Cowan (08 Jul 2019 04:56 UTC)
Re: Escape via unhygienic macros Marc Nieper-Wißkirchen (04 Jul 2019 20:26 UTC)
Re: Escape via unhygienic macros Lassi Kortela (14 Jul 2019 15:41 UTC)
Re: Escape via unhygienic macros John Cowan (14 Jul 2019 17:59 UTC)

Re: Escape via unhygienic macros Phil Hofer 04 Jul 2019 17:42 UTC
> Well, untrusted by whom and for what?  Gcc is certainly not verified correct (and verified-correct programs often have bugs due to errors in the specification), yet as a human matter I trust it not to mung my computer and in fact to compile my C programs correctly, if somewha nastily.

But the difference between GCC and this SRFI is that there is
a pretty clear definition of what behavior is _expected_ to be
safe. ANSI C doesn't provide guarantees about all behavior, but
it does provide guarantees about specific pieces of behavior,
and additionally points out which pieces of behavior are notably
unspecified. Consequently, we can determine whether or not an
implementation is actually buggy or just takes liberties with
what the standard says is undefined behavior.

Conversely, this SRFI, by your own admission, has "no guarantees."
Consequently, an implementation that is no safer than 'eval' is
today is perfectly conformant. This would likely be the case in
at least Chicken and Chibi, which AFAICT are the only two R7RS
implementations that are widely used a the moment.

Safety features are supposed to provide guarantees. That doesn't
mean they always hold up their end of the bargain (bugs abound!),
but it does mean that we can reason about what the behavior
_should_ be.

- Phil