On Monday, 1 July 2013 at 06:28:57 UTC, monarch_dodra wrote:
On Monday, 1 July 2013 at 02:53:24 UTC, Jonathan M Davis wrote:
On Monday, July 01, 2013 04:37:43 Mehrdad wrote:
On Sunday, 30 June 2013 at 20:49:28 UTC, Peter Alexander
wrote:
> sometimes faster
Would love an example that demonstrates it!
Anything involving taking a lot of substrings is likely to be
faster in D
thanks to slices (which is one of the main reasons that
Tango's xml parser is
so lightning fast). You could write the same code in C++, but
it's harder,
because slices aren't built-in, and you have no GC, probably
forcing you to
create your own string type that supports slices and does
reference counting
if you want a similar effect.
- Jonathan M Davis
Well... in "C++", a slice is called an iterator pair. If you
just:
typedef std::pair<std::string::const_iterator, const_itrator>
string_slice;
Then there is no reason you can't do it... The only "problem"
is that it is not a standard semantic in C++, so nobody ever
thinks about doing this, and much less actually ever does it.
There is a *little* bit of barrier to entry too.
I've done this once about two years ago (before I knew about D)
because I needed a "subview" of a vector. My typedef's name was
"shallow_vector". It was a fun experience given I didn't know
about the range concept back then :)
In any case, if you *do* want to go there, it doesn't really
require you creating that much new stuff, especially not your
own string/vector type.
Boost recently added string_ref, "a non-owning reference to a
string":
http://www.boost.org/doc/libs/1_53_0/libs/utility/doc/html/string_ref.html
Gets you something similar to slices but is inherently more
dangerous to use than GC backed slices.
