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digitalmars.D - Rune strings. Like in Go.

reply Alexey <invalid email.address> writes:
Can we have them in D? :)
Sep 30 2021
next sibling parent reply Paul Backus <snarwin gmail.com> writes:
On Thursday, 30 September 2021 at 20:44:54 UTC, Alexey wrote:

 Can we have them in D? :)


We have them already. :) What Go calls a "rune" is called a 
`dchar` in D, and a string of them is a `dchar[]`.
Sep 30 2021
parent reply Alexey <invalid email.address> writes:
On Thursday, 30 September 2021 at 20:57:34 UTC, Paul Backus wrote:

 On Thursday, 30 September 2021 at 20:44:54 UTC, Alexey wrote:

 Can we have them in D? :)


 We have them already. :) What Go calls a "rune" is called a 
 `dchar` in D, and a string of them is a `dchar[]`.


Go's runes and D's dchars - have different behavior.
Go's rune string, being converted to byte array like so 
`[]byte(string_var)` and saved to file - results in UTF-8, while 
dchar is UTF-32.

this means - the frequent conversions between string and dstring 
in D is required for confortable work with unicode.
Sep 30 2021
next sibling parent "H. S. Teoh" <hsteoh quickfur.ath.cx> writes:
On Thu, Sep 30, 2021 at 10:47:25PM +0000, Alexey via Digitalmars-d wrote:

 On Thursday, 30 September 2021 at 20:57:34 UTC, Paul Backus wrote:

 On Thursday, 30 September 2021 at 20:44:54 UTC, Alexey wrote:

 Can we have them in D? :)


 
 We have them already. :) What Go calls a "rune" is called a `dchar`
 in D, and a string of them is a `dchar[]`.


 
 Go's runes and D's dchars - have different behavior.
 Go's rune string, being converted to byte array like so
 `[]byte(string_var)` and saved to file - results in UTF-8, while dchar
 is UTF-32.
 
 this means - the frequent conversions between string and dstring in D
 is required for confortable work with unicode.


This is not true. D strings are autodecoded with Phobos range functions,
i.e., if you iterate over a string with Phobos, you will get a stream of
dchars without having to convert the encoding.

(Ironically enough, autodecoding is regarded as a bad thing!)

Also, IIRC, writing a stream of dchars to a string sink, e.g.,
appender!string, will automatically encode into UTF-8, so no explicit
conversion is needed afterwards.


T

-- 
If you look at a thing nine hundred and ninety-nine times, you are perfectly
safe; if you look at it the thousandth time, you are in frightful danger of
seeing it for the first time. -- G. K. Chesterton
Sep 30 2021
prev sibling parent jfondren <julian.fondren gmail.com> writes:
On Thursday, 30 September 2021 at 22:47:25 UTC, Alexey wrote:

 Go's rune string, being converted to byte array like so 
 `[]byte(string_var)` and saved to file - results in UTF-8, 
 while dchar is UTF-32.


You're explicitly asking for a byte cast and instead of a byte 
cast you get a reencoding? You might prefer that because it's 
familiar, but that's a really confusing thing to do. 
`std.string.representation` meanwhile turns a `dchar[]` into an 
`uint[]`.

And to get UTF-8 in a file, just write the string:

```d
import std;

void write() {
     string noel = "no\u0308el";
     dstring dstr = noel.toUTF32;

     File("a", "w").writeln(noel);
     File("b", "w").writeln(dstr);
}

void main() {
     write;
     ubyte[] fromA = cast(ubyte[]) read("a");
     ubyte[] fromB = cast(ubyte[]) read("b");

     assert(fromA == fromB);
     writeln(fromA, "\n", fromB);
}
```

output:

```
[110, 111, 204, 136, 101, 108, 10]
[110, 111, 204, 136, 101, 108, 10]
```
Sep 30 2021
prev sibling next sibling parent Basile B. <b2.temp gmx.com> writes:
On Thursday, 30 September 2021 at 20:44:54 UTC, Alexey wrote:

 Can we have them in D? :)


do you want a verbatim about runs on IRC ?
Sep 30 2021
prev sibling parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 9/30/21 1:44 PM, Alexey wrote:

 Can we have them in D? :)


Looks like Go "could" have them. ;)

Ali
Sep 30 2021