Characters in D
user4567 at 1234.te
Sat Nov 2 20:49:15 UTC 2019
On Saturday, 2 November 2019 at 18:45:50 UTC, Eugene wrote:
> On Saturday, 2 November 2019 at 18:26:57 UTC, user4567 wrote:
>> On Saturday, 2 November 2019 at 18:09:01 UTC, Eugene wrote:
>>> On Saturday, 2 November 2019 at 15:54:02 UTC, Adam D. Ruppe
>>>> On Saturday, 2 November 2019 at 15:44:49 UTC, Eugene wrote:
>>>>> "Variable of type char can only hold letters that are in
>>>>> the ASCII table". (section 15.4 Character literals)
>>>>> So why there is executed next code?
>>>> The individual char can only hold those, but a group of
>>>> chars can hold anything.
>>>>> char cyrillics = "привет".dup;
>>>> this works because the "string" has multi-char groupings
>>>>> char cyrillics = ['п', 'р', 'и', 'в', 'е', 'т']; //not
>>>> and this doesn't because you are specifying individual items
>>>> there so it can't just spread them across multiple bytes
>>> Um. It is not obvious at all. What's mean spread across
>>> multiple bytes?
>> it's encoded in UTF-8, for example the **string** "п" takes 2
>> `char`s, although it's only one grapheme.
>> assert("привет".length == 12); // encoded as UTF-8
>> assert("привет"d.length == 6); // decoded, each dchar is 4
>> bytes and can contain a cyrilic character.
> "п" is represented by two code units, but "п"d is represented
> by one code point, therefore 12 and 6 respectively. Function
> dup manipulates by code units and represents their to char.
Oh I see what you ask, in first place we thought that you didn't
get the implication of encoding. So it's just a rule. If you use
`char` literals they must be ascii.
The rationale could be that this rule avoid bad surprises on the
length of the array, otherwise I cant imagine anything else. ONly
original designers (so Bright) must know the exact rationale...
cant say more.
More information about the Digitalmars-d