On Thursday, 6 November 2014 at 10:52:32 UTC, Ivan Kazmenko wrote:
On Wednesday, 5 November 2014 at 13:34:05 UTC, Marc Schütz
wrote:
On Wednesday, 5 November 2014 at 12:54:03 UTC, Ivan Kazmenko
wrote:
Hi!
This gives an error (cannot deduce template function from
argument types):
-----
import std.algorithm;
void main () {
char [] c;
sort (c);
}
-----
Why is "char []" so special that it can't be sorted?
For example, if I know the array contains only ASCII
characters, sorting it sounds no different to sorting an "int
[]".
Hmm... this doesn't work either:
import std.algorithm;
import std.utf;
void main () {
char [] c;
sort (c.byCodeUnit);
}
But IMO it should.
So, you imply that to use a char array as a RandomAccessRange,
I have to use byCodeUnit? (and it should work, but doesn't?)
Yes. H.S. Teoh has already submitted a PR to fix it.
Fine, but how does one learn that except by asking here?
Googling did not produce meaningful results for me.
For example, isRandomAccessRange[0] states the problem:
-----
Although char[] and wchar[] (as well as their qualified
versions including string and wstring) are arrays,
isRandomAccessRange yields false for them because they use
variable-length encodings (UTF-8 and UTF-16 respectively).
These types are bidirectional ranges only.
-----
but does not offer a solution. If (when) byCodeUnit does
really provide a random-access range, it would be desirable to
have it linked where the problem is stated.
[0] http://dlang.org/phobos/std_range.html#.isRandomAccessRange
I agree. But how should it be implemented? We would have to
modify algorithms that require an RA range to also accept char[],
but then print an error message with the suggestion to use
byCodeUnit. I think that's not practicable. Any better ideas?
