http://d.puremagic.com/issues/show_bug.cgi?id=5630

On Sun, 20 Feb 2011 17:10:28 -0500, Jacob Carlborg <doob@me.com> wrote:

> On 2011-02-20 21:30, Steven Schveighoffer wrote:
>> On Sun, 20 Feb 2011 13:40:08 -0500, Jacob Carlborg <doob@me.com> wrote:
>>
>>
>>>
>>> I'm confused about how someone can implement a library like this.
>>> Every time I try to use D2 it's just a PITA to use. I've used D1 and
>>> Tango for several years and had no problem with that.
>>
>> Strings are a sore spot for me, I think the current implementation is a
>> hack which leaves much to be desired. However, it seems that Andrei
>> believes the current implementation is not only decent, but actually
>> better than any alternative.
>>
>>> I assume this has been discussed, did that resolve in any plans to
>>> solve this?
>>
>> I am, in my spare time, working on a way to represent strings that
>> allows strings to be what they are and arrays of chars or wchars to be
>> what they are. It is not finished yet, but I've put forth a couple
>> incomplete examples. Search for [review] on the D news group.
>>
>> Things have gotten quite more complex when I realized that dchar is
>> actually not the most natural "element" of a string, since a dchar
>> doesn't represent a visible character (or one that a human would
>> interpret as a single character) and also that the exact same string can
>> be sometimes represented by two distinct sequences of dchars. When I can
>> finish the proposed change, I will probably try integrating it with
>> Phobos to see how well it works.
>>
>> -Steve
>
> Oh, I remember that thread(s). It got so overly complicated so I stopped reading it.

Yeah, UTF is so overly complicated, it's difficult to properly implement it.

-Steve

On Sun, 20 Feb 2011 15:23:29 -0500, Steven Schveighoffer wrote:

> On Sun, 20 Feb 2011 14:51:10 -0500, bearophile <bearophileHUGS@lycos.com> wrote:
> 
>> Jacob Carlborg:
>>
>>> Every time I try to use D2 it's just a PITA to use. I've used D1 and
>>> Tango for
>>> several years and had no problem with that.
>>
>> I use this thread to ask regarding one specific little problem I have with strings. I want to generate a random string of AB using the array, map, etc, this looks like a possible implementation (in std.random there is no choice() function yet):
>>
>>
>> import std.stdio, std.random, std.string, std.algorithm, std.range;
>> void main() {
>>     auto m = map!((i){ return "AB"[uniform(0,2)]; })(iota(10)); string
>>     s = join(array(m));
>>     writeln(s);
>> }
>>
>>
>> It gives this error:
>> ...\dmd\src\phobos\std\array.d(62): Error: result[i] isn't mutable
>> test.d(5): Error: template instance
>> std.array.array!(Map!(__dgliteral1,Iota!(int,uint))) error
>> instantiating
>>
>> What's the right way to write it in D?
>>
>> The same code in Python2.x:
>>
>> from random import choice
>> s = "".join(choice("AB") for _ in xrange(10)) print s
> 
> Just a blind guess, I have not tested, but maybe it's because the compiler is using const(char) as the return type for your delegate literal since you never specify one?

It's probably using immutable(char) since that's the element type of "AB".

-Lars