From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Philipp Stephani <p.stephani2@gmail.com>
Cc: "Mattias Engdegård" <mattiase@acm.org>,
"Paul Eggert" <eggert@cs.ucla.edu>,
"Andrea Corallo" <andrea_corallo@yahoo.it>,
42147@debbugs.gnu.org
Subject: bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations?
Date: Mon, 10 Aug 2020 18:10:39 -0400 [thread overview]
Message-ID: <jwvsgcuyx18.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <CAArVCkSVt2k8zfVG+aBErAUt2=4PygYkwZ8F6NukKJ+itR1E_g@mail.gmail.com> (Philipp Stephani's message of "Mon, 10 Aug 2020 15:42:48 +0200")
> Arguments relating to probabilities ("most users", "vast majority",
> "rare") don't really apply here, as the discussion is about
> correctness. A pure function must be pure 100% of the time, no
> exceptions allowed. `package-get-version' can't possibly be pure: it
> doesn't take any argument, so if it were pure, it would have to return
> a constant in the mathematical sense.
It's a borderline case: it's designed such that if the compiler
pre-evaluates it, the result will indeed be the same as if it were
evaluated later at run-time.
So it's correct w.r.t "allow constant-folding", even tho it's not
"pure".
Stefan
next prev parent reply other threads:[~2020-08-10 22:10 UTC|newest]
Thread overview: 98+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1583748933.1069307.1593556032592.ref@mail.yahoo.com>
2020-06-30 22:27 ` bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations? Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-06-30 23:14 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-01 12:46 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-01 12:44 ` Mattias Engdegård
2020-07-01 16:08 ` Mattias Engdegård
2020-07-01 21:31 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-02 10:26 ` Mattias Engdegård
2020-07-02 10:59 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-02 12:46 ` Mattias Engdegård
2020-07-02 13:56 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-02 14:51 ` Mattias Engdegård
2020-07-02 15:32 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-02 15:49 ` Stefan Monnier
2020-07-02 18:01 ` Mattias Engdegård
2020-07-02 18:55 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-02 19:38 ` Stefan Monnier
2020-07-02 20:09 ` Paul Eggert
2020-07-03 9:32 ` Mattias Engdegård
2020-07-03 13:39 ` bug#42147: Hash-consing bignums (was: bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations?) Stefan Monnier
2020-07-02 20:31 ` bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations? Paul Eggert
2020-07-02 21:41 ` Stefan Monnier
2020-07-02 23:16 ` Paul Eggert
2020-07-03 8:32 ` Mattias Engdegård
2020-07-03 13:11 ` Stefan Monnier
2020-07-03 18:35 ` Mattias Engdegård
2020-07-03 18:43 ` Mattias Engdegård
2020-07-03 19:05 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-04 14:58 ` Mattias Engdegård
2020-07-04 15:06 ` Stefan Monnier
2020-07-04 16:13 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-05 13:00 ` Mattias Engdegård
2020-07-05 13:16 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-06 17:20 ` Mattias Engdegård
2020-07-06 21:23 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-07 15:54 ` Mattias Engdegård
2020-07-07 16:24 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-07 16:55 ` Mattias Engdegård
2020-07-07 17:42 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-08 19:14 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-08 21:25 ` Mattias Engdegård
2020-07-08 22:19 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-09 10:20 ` Mattias Engdegård
2020-07-09 12:47 ` Stefan Monnier
2020-07-09 12:57 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-09 14:35 ` Stefan Monnier
2020-07-09 15:19 ` Paul Eggert
2020-07-09 15:37 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-05 15:26 ` Mattias Engdegård
2020-07-03 18:31 ` Paul Eggert
2020-07-03 18:47 ` Mattias Engdegård
2020-07-04 15:57 ` Paul Eggert
2020-07-04 16:15 ` Eli Zaretskii
2020-07-04 16:27 ` Paul Eggert
2020-07-04 16:33 ` Stefan Monnier
2020-07-04 16:44 ` Mattias Engdegård
2020-07-04 17:00 ` Paul Eggert
2020-07-04 18:37 ` Pip Cet
2020-07-04 21:05 ` Stefan Monnier
2020-07-04 22:25 ` Pip Cet
2020-07-05 2:38 ` Eli Zaretskii
2020-07-05 8:28 ` Paul Eggert
2020-07-05 8:39 ` Andreas Schwab
2020-07-05 14:47 ` Eli Zaretskii
2020-07-05 15:30 ` Stefan Monnier
2020-07-06 0:14 ` Paul Eggert
2020-07-05 15:11 ` Stefan Monnier
2020-07-06 0:10 ` Paul Eggert
2020-07-05 9:56 ` Paul Eggert
2020-07-05 10:03 ` Andrea Corallo via Bug reports for GNU Emacs, the Swiss army knife of text editors
2020-07-05 23:57 ` Paul Eggert
2020-07-04 19:01 ` Mattias Engdegård
2020-07-04 17:10 ` Eli Zaretskii
2020-07-04 19:26 ` Paul Eggert
2020-07-02 19:09 ` Philipp Stephani
2020-07-03 9:25 ` Mattias Engdegård
2020-07-25 17:09 ` Philipp Stephani
2020-07-25 18:10 ` Stefan Monnier
2020-07-25 20:03 ` Philipp Stephani
2020-07-25 20:07 ` Stefan Monnier
2020-07-25 20:11 ` Philipp Stephani
2020-07-25 21:00 ` Mattias Engdegård
2020-07-25 21:29 ` Stefan Monnier
2020-07-25 21:39 ` Philipp Stephani
2020-07-25 22:27 ` Stefan Monnier
2020-07-29 12:53 ` Philipp Stephani
2020-07-29 14:28 ` Stefan Monnier
2020-07-25 21:54 ` Mattias Engdegård
2020-07-25 22:30 ` Stefan Monnier
2020-07-26 9:05 ` Mattias Engdegård
2020-07-29 16:03 ` Mattias Engdegård
2020-07-29 20:39 ` Stefan Monnier
2020-08-03 15:07 ` Mattias Engdegård
2020-08-10 13:39 ` Philipp Stephani
2020-08-10 22:07 ` Stefan Monnier
2020-08-10 13:42 ` Philipp Stephani
2020-08-10 22:10 ` Stefan Monnier [this message]
2020-07-29 13:10 ` Philipp Stephani
2020-07-25 21:09 ` Stefan Monnier
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