grauzone wrote:
Andrei Alexandrescu wrote:
grauzone wrote:
dsimcha wrote:
== Quote from Walter Bright (newshou...@digitalmars.com)'s article
Andrei Alexandrescu wrote:
2. The global random generator will be allocated per thread. Are you
cool with this too?
That could have speed problems with a tight loop accessing thread
local
storage.
I don't think this matters, since for apps that really need it, a
RNG can be
explicitly passed in. This is purely a convenience feature for when
you want
random number generation to "just work" even if it's not the most
efficient thing
in the world. Also, checking thread_needLock() is dirt cheap, in my
experience
faster than accessing TLS. You could also have a global, non-thread
local RNG
that is used if a check to thread_needLock() returns false.
I don't understand this. If implemented right (D2.0 or gcc thread
variables), TLS can be as fast as a normal global variable. You only
need an additional check (a simple if()) to lazily initialize the RNG.
Regarding "just work": it seems D's philosophy, to prefer to do the
simple and "right" thing instead of raw efficiency, seems to be
abandoned. Like std.algorithm uses weird string mixins, and the
predicate is a template argument instead of a normal one (that's IMHO).
Well I can only welcome the return of persistent flamebaiting to this
group. D's philosophy is to prefer to do the right thing, even when that
Why is it "flamebaiting" when I say my opinion? Others are doing it too.
Here, I even used "IMHO" to mark that this is my opinion, and not
necessarily some kind of objective truth.
And if you think I'm trolling, then you obviously shouldn't take the
bait. Else you'd add quite some fuel for an actual flamewar. I really
don't understand this.
Yah, you're right. I shouldn't have answered, and my answer ended up
going firmly further out of line. I am sorry about that. If you care for
my reasons, please read on.
Now I do understand in the end you're doing nothing but stating an
opinion, which is of course what we do most of the time. All I'm saying
is that it's more beneficial to discuss an opinion of the form:
"I prefer froobenglobs to std.brooblenglabs. I think std.brooblenglabs
are unnecessarily complicated with too few redeeming qualities. In
contrast, froobenglobs have the simplicity given by using the universal
trilegate feature, and their inherent loss of quantic traction is
negligible. So I suggest froobenglobs to be considered as a supplement
or replacement for a future std.brooblenglabs."
This is an opinion that can be discussed because it brings supporting
arguments that can in turn be debated. Many good things transpire that
way. Should we reach the conclusion that our views on the matter differ
in some irreducible manner, we'll still be gained from the discussion.
Contrast this with not an opinion, but an umbrella statement that
implicitly assumes a number of opinions are true facts:
"Everything about C++, language and libraries, reeks of bad design"
(this is how I read your ironic statement to the contrary).
or
"It looks like D's philosophy to do the simple and right thing instead
of raw efficiency has been abandoned."
This (and the subsequent example) after I've spent time on several
occasions on explaining you how and why exactly pass-by-delegate is not
defensible versus pass-by-alias, which includes pass-by-delegate in its
jeans pocket. The "IMHO" license you use does little to help such
statements. I agree the odd rules of pass-by-string may seem unsavory to
some, but please agree with me that there is little in the way of a
salient answer that could be given to the umbrella statement above.
This means that, had std.algorithm taken the "normal" route, it would
have been plenty useless for any serious needs. Not taking the
"normal" route means that its abstractions rival hand-tuned code so I
can use them without worrying they will come unglued when shown a real
challenge.
That's what I said. You preferred this design because it's faster. One
can agree or disagree if this approach introduces "syntax artifacts" or
if it violates KISS or whatever. Everything has its pros and cons. I
just said I disagree.
I preferred that design not only because it's faster, but also because
it _includes_ *all* /benefits/ of the "slower" rule of pass-by-delegate,
i.e. it can be slower and more flexible if that's what's needed. The
only "cost" is a minor change in usage syntax. Essentially I think D has
hit mother lode with the local instantiation feature because it has all
the benefits and next to no problem. I sincerely believe it will be
instrumental to the success of D.
Given its advantages, it would be an extraordinary uphill battle to
argue that pass-by-alias with local instantiation is a lesser design.
What pushed my button is not that you undertook said battle, but that
you made statements that imply you've already won it.
Also, dsimcha said:
> This is purely a convenience feature for when you want
> random number generation to "just work" even if it's not the most
> efficient thing
> in the world.
I agree to him. If you need efficiency, you can write your own code or
use a highly specialized library fit for the job. Most users probably
wouldn't rely on the standard library if they're optimizing their code.
Well, you see, here's where we can "agree to disagree" (as much as I
dislike the PCness of the phrase). IMHO, if most users in search for
efficiency need to roll their own counterparts of the abstractions
provided by Phobos, I've majorly wasted my time. Costly abstractions are
a dime a dozen. I have nothing but contempt for them. Every dog language
has them in spades. The real challenge is not to write sort in three
lines. It's to write it in three lines and have it beat the 2000 lines
sort. (Alas, we're not there yet.)
> As long as the user _can_ write his own code, the standard library
> should prefer to be simple and easy to use. It also prevents bitrot,
> bloat, and incomprehensible library code.
This approach seems to be pushing bitrot, bloat, and incomprehensibility
into the user code, while keeping the library a collection of useless
toys. Hardly an approach I'd go for. I am sorry. I just disagree.
Andrei
