Sergey Gromov:
>Different languages require different idioms, that's my strong opinion.<
I agree a lot, but it seems I need quite more than one year to learn most D
idioms. I am just ignorant and willing to learn.
> One really important benchmark would be something like this:
> results
> D: 5.52s
> C++: 4.96s
I have tested the following D and C++ code (note that the C++ code is a single
file now):
// D code
class TerminateException {}
void do_stuff(int i) {
if (i == 1_000_000_000)
throw new TerminateException;
}
void main() {
for (int i; ; i++) {
try {
do_stuff(i);
} catch (TerminateException e) {
break;
}
}
}
// C++ code
struct TerminateException {};
void do_stuff(int i) {
if (i == 1000000000)
throw TerminateException();
}
int main() {
for (int i = 0; ; i++) {
try {
do_stuff(i);
} catch (const TerminateException & e) {
break;
}
}
return 0;
}
My timings are:
N = 1_000_000_000:
C++: 0.06 s
D: 5.10 s
Compiled with:
CPU: Core 2 at 2 GHz, 2 GB Ram, Windows XP.
D code compiled with:
DMD v1.041
-O -release -inline
C++ code compiled with:
gcc version 4.3.3-dw2-tdm-1 (GCC)
-O3 -s
-------------------------------
grauzone:
> Alternatively, one could introduce nullable types:
> int? toInt(char[] s);
> The use of nullable value type int? would be a bit similar to object
> references in D. One can check it for null-ness, and using a null value
> raises a special exception.
> As a third way, one could simply return a tuple:
> (bool, int) toInt(char[] s);
That's nice enough. The return value can be a struct (can contains the result
plus a bool (or int) error flag/value).
>>Python3 also removes the find() method of strings, and leaves only the
>>index() method, that is like find(), but raise ValueError when the substring
>>is not found. So you are forced to use exceptions here too.<<
>I'm shocked. That's beyond stupid. Didn't they consider ease of use?<
As usual you must know many details specific of that situation before
commenting on a decision (I like the old -1 return value, but Python designers
are often able to find design ideas better than my ones).
Here are some discussions on the rationale:
http://mail.python.org/pipermail/python-dev/2005-August/055704.html
http://mail.python.org/pipermail/python-dev/2005-August/055705.html
http://mail.python.org/pipermail/python-dev/2005-August/055708.html
http://mail.python.org/pipermail/python-dev/2005-August/055711.html
http://mail.python.org/pipermail/python-dev/2005-August/055712.html
http://mail.python.org/pipermail/python-dev/2005-August/055717.html
http://mail.python.org/pipermail/python-dev/2005-August/055740.html
http://mail.python.org/pipermail/python-dev/2005-August/055748.html
http://mail.python.org/pipermail/python-dev/2005-August/055754.html
And the discussion doesn't stop there...
Bye and thank you,
bearophile
