On 11/22/10 11:22 AM, Steven Schveighoffer wrote:
On Mon, 22 Nov 2010 12:07:55 -0500, Andrei Alexandrescu
<seewebsiteforem...@erdani.org> wrote:
On 11/22/10 9:37 AM, Steven Schveighoffer wrote:
On Sun, 21 Nov 2010 23:56:17 -0500, Andrei Alexandrescu
<seewebsiteforem...@erdani.org> wrote:
If you want to work with arrays, use a[0] to access the front, a[$ -
1] to access the back, and a = a[1 .. $] to chop off the first element
of the array. It is not AT ALL natural to mix those with a.front,
a.back etc. It is not - why? because std.range defines them with
specific meanings for arrays in general and for arrays of characters
in particular. If you submit to use std.range's abstraction, you
submit to using it the way it is defined.
I want to use char[] as an array. I want to sort the array, how do I do
this? (assume array.sort as a property is deprecated, as it should be)
Why do you want to sort an array of char?
You're dodging the question. You claim that if I want to use it as an
array, I use it as an array, if I want to use it as a range, use it as a
range. I'm simply pointing out why you can't use it as an array --
because phobos treats it as a bidirectional range, and you can't force
it to do what you want.
Of course you can. After you were to admit that it makes next to no
sense to sort an array of code units, I would have said "well if somehow
you do imagine such a situation, you achieve that by saying what you
means: cast the char[] to ubyte[] and sort that".
More points -- what about a redblacktree!(char)? Is that 'invalid'? I
mean, it's automatically sorted, so what should I do, throw an error if
you try to build one?
No, it still has well-defined semantics. It just doesn't have much sense
to it. Why would you use a redblacktree of char? Probably you want one
of ubyte, so then why don't you say so?
Is an Array!char a string? What about an SList!char?
Depends on how Array or SList are defined. D chose to convey char[] and
wchar[] specific meaning revealing that they are sequences of code
points, i.e. Unicode strings.
The thing is, *only* when one wants to create strings, does one want to
view the data type as a bidirectional string. When one wants to deal
with chars as an element of a container, I don't want to be restricted
to utf requirements.
If you don't want to be restricted to utf requirements, use ubyte and
ushort. You're saying "I want to use UTF code points without any
associated UTF meaning".
FWIW, I deal in ASCII pretty much exclusively, so sorting an array of
char is not out of the question.
Example?
You might say "oh, well that's stupid!"
but then so is using the index operator on a char[] array, no? I see no
difference.
There is a difference. Often in a loop you know the index at which a
code point starts.
I'm going to drop out of this discussion in order to develop a viable
alternative to using arrays to represent strings. Then we can discuss
the merits/drawbacks of such a type. I think it will be simple to build.
I think that's a great idea.
Andrei
