Re: Bug? 0 is less than -10
On Wednesday, 7 October 2015 at 02:53:32 UTC, Steven Schveighoffer wrote: On 10/6/15 7:21 PM, Laeeth Isharc wrote: could we have ssize_t defined in phobos somewhere so your code ends up being portable ;) (It's trivial to do, obviously). ptrdiff_t -Steve It seems unnatural to use such a name when the variable has nothing to do with pointers - it doesn't contribute to the readability. Yes, it's trivial, but small things cumulatively matter. Adam tends to use int and when that gets mixed up with an auto size_t (eg via length) then his code doesn't compile on 64 bit. And if it happens with his code, you can imagine this isn't a problem that inexperienced users never encounter.
Re: Bug? 0 is less than -10
On 10/6/15 7:21 PM, Laeeth Isharc wrote: could we have ssize_t defined in phobos somewhere so your code ends up being portable ;) (It's trivial to do, obviously). ptrdiff_t -Steve
Re: AWS API Dlang, hmac sha256 function.
On 07/10/15 3:18 PM, holo wrote:
Congrats on getting it working!
@Rikki Thanks :)
I was trying to write my own lib from beginning based on examples but
after some time i resign from that idea (will back to it when i will
have some more experience) and right now im trying to customize that one
from link which yawniek paste:
https://github.com/yannick/vibe-aws/blob/master/source/vibe/aws/sigv4.d
I removed import from vibe.d library and copy/paste missed functions
formEncode and filterURLEncode (BTW: what that "(R)" mean in it?
filterURLEncode(R)(ref R dst, ..., ..) ).
If you see a template argument (which R is) it is typically meant for a
range. In this case an output range. Although there should be
isOutputRange!R in an template if condition, to check this.
Next thing what i did was to replace hmac function to use hmac module
from newest library. Now whole code looks like this:
module sigv4;
import std.array;
import std.algorithm;
import std.digest.sha;
import std.range;
import std.stdio;
import std.string;
import std.format;
import std.digest.hmac;
const algorithm = "AWS4-HMAC-SHA256";
void filterURLEncode(R)(ref R dst, string str, string allowed_chars =
null, bool form_encoding = false)
{
while( str.length > 0 ) {
switch(str[0]) {
case ' ':
if (form_encoding) {
dst.put('+');
break;
}
goto default;
case 'A': .. case 'Z':
case 'a': .. case 'z':
case '0': .. case '9':
case '-': case '_': case '.': case '~':
dst.put(str[0]);
break;
default:
if (allowed_chars.canFind(str[0])) dst.put(str[0]);
else formattedWrite(dst, "%%%02X", str[0]);
}
str = str[1 .. $];
}
}
string formEncode(string str, string allowed_chars = null)
@safe {
auto dst = appender!string();
dst.reserve(str.length);
filterURLEncode(dst, str, allowed_chars, true);
return dst.data;
}
struct CanonicalRequest
{
string method;
string uri;
string[string] queryParameters;
string[string] headers;
ubyte[] payload;
}
string canonicalQueryString(string[string] queryParameters)
{
alias encode = formEncode;
string[string] encoded;
foreach (p; queryParameters.keys())
{
encoded[encode(p)] = encode(queryParameters[p]);
}
string[] keys = encoded.keys();
sort(keys);
return keys.map!(k => k ~ "=" ~ encoded[k]).join("&");
}
string canonicalHeaders(string[string] headers)
{
string[string] trimmed;
foreach (h; headers.keys())
{
trimmed[h.toLower().strip()] = headers[h].strip();
}
string[] keys = trimmed.keys();
sort(keys);
return keys.map!(k => k ~ ":" ~ trimmed[k] ~ "\n").join("");
}
string signedHeaders(string[string] headers)
{
string[] keys = headers.keys().map!(k => k.toLower()).array();
sort(keys);
return keys.join(";");
}
string hash(T)(T payload)
{
auto hash = sha256Of(payload);
return hash.toHexString().toLower();
}
string makeCRSigV4(CanonicalRequest r)
{
auto cr =
r.method.toUpper() ~ "\n" ~
(r.uri.empty ? "/" : r.uri) ~ "\n" ~
canonicalQueryString(r.queryParameters) ~ "\n" ~
canonicalHeaders(r.headers) ~ "\n" ~
signedHeaders(r.headers) ~ "\n" ~
hash(r.payload);
return hash(cr);
}
unittest {
string[string] empty;
auto r = CanonicalRequest(
"POST",
"/",
empty,
["content-type": "application/x-www-form-urlencoded;
charset=utf-8",
"host": "iam.amazonaws.com",
"x-amz-date": "20110909T233600Z"],
cast(ubyte[])"Action=ListUsers&Version=2010-05-08");
auto sig = makeCRSigV4(r);
assert(sig ==
"3511de7e95d28ecd39e9513b642aee07e54f4941150d8df8bf94b328ef7e55e2");
}
struct SignableRequest
{
string dateString;
string timeStringUTC;
string region;
string service;
CanonicalRequest canonicalRequest;
}
string signableString(SignableRequest r) {
return algorithm ~ "\n" ~
r.dateString ~ "T" ~ r.timeStringUTC ~ "Z\n" ~
r.dateString ~ "/" ~ r.region ~ "/" ~ r.service ~
"/aws4_request\n" ~
makeCRSigV4(r.canonicalRequest);
}
unittest {
string[string] empty;
SignableRequest r;
r.dateString = "20110909";
r.timeStringUTC = "233600";
r.region = "us-east-1";
r.service = "iam";
r.canonicalRequest = CanonicalRequest(
"POST",
"/",
empty,
["content-type": "application/x-www-form-urlencoded;
charset=utf-8",
"host": "iam.amazonaws.com",
"x-amz-date": "20110909T233600Z"],
cast(ubyte[])"Action=ListUsers&Version=2010-05-08");
auto sampleString =
algorithm ~ "\
Re: AWS API Dlang, hmac sha256 function.
Congrats on getting it working!
@Rikki Thanks :)
I was trying to write my own lib from beginning based on examples
but after some time i resign from that idea (will back to it when
i will have some more experience) and right now im trying to
customize that one from link which yawniek paste:
https://github.com/yannick/vibe-aws/blob/master/source/vibe/aws/sigv4.d
I removed import from vibe.d library and copy/paste missed
functions formEncode and filterURLEncode (BTW: what that "(R)"
mean in it? filterURLEncode(R)(ref R dst, ..., ..) ).
Next thing what i did was to replace hmac function to use hmac
module from newest library. Now whole code looks like this:
module sigv4;
import std.array;
import std.algorithm;
import std.digest.sha;
import std.range;
import std.stdio;
import std.string;
import std.format;
import std.digest.hmac;
const algorithm = "AWS4-HMAC-SHA256";
void filterURLEncode(R)(ref R dst, string str, string
allowed_chars = null, bool form_encoding = false)
{
while( str.length > 0 ) {
switch(str[0]) {
case ' ':
if (form_encoding) {
dst.put('+');
break;
}
goto default;
case 'A': .. case 'Z':
case 'a': .. case 'z':
case '0': .. case '9':
case '-': case '_': case '.': case '~':
dst.put(str[0]);
break;
default:
if (allowed_chars.canFind(str[0]))
dst.put(str[0]);
else formattedWrite(dst, "%%%02X", str[0]);
}
str = str[1 .. $];
}
}
string formEncode(string str, string allowed_chars = null)
@safe {
auto dst = appender!string();
dst.reserve(str.length);
filterURLEncode(dst, str, allowed_chars, true);
return dst.data;
}
struct CanonicalRequest
{
string method;
string uri;
string[string] queryParameters;
string[string] headers;
ubyte[] payload;
}
string canonicalQueryString(string[string] queryParameters)
{
alias encode = formEncode;
string[string] encoded;
foreach (p; queryParameters.keys())
{
encoded[encode(p)] = encode(queryParameters[p]);
}
string[] keys = encoded.keys();
sort(keys);
return keys.map!(k => k ~ "=" ~ encoded[k]).join("&");
}
string canonicalHeaders(string[string] headers)
{
string[string] trimmed;
foreach (h; headers.keys())
{
trimmed[h.toLower().strip()] = headers[h].strip();
}
string[] keys = trimmed.keys();
sort(keys);
return keys.map!(k => k ~ ":" ~ trimmed[k] ~ "\n").join("");
}
string signedHeaders(string[string] headers)
{
string[] keys = headers.keys().map!(k => k.toLower()).array();
sort(keys);
return keys.join(";");
}
string hash(T)(T payload)
{
auto hash = sha256Of(payload);
return hash.toHexString().toLower();
}
string makeCRSigV4(CanonicalRequest r)
{
auto cr =
r.method.toUpper() ~ "\n" ~
(r.uri.empty ? "/" : r.uri) ~ "\n" ~
canonicalQueryString(r.queryParameters) ~ "\n" ~
canonicalHeaders(r.headers) ~ "\n" ~
signedHeaders(r.headers) ~ "\n" ~
hash(r.payload);
return hash(cr);
}
unittest {
string[string] empty;
auto r = CanonicalRequest(
"POST",
"/",
empty,
["content-type": "application/x-www-form-urlencoded;
charset=utf-8",
"host": "iam.amazonaws.com",
"x-amz-date": "20110909T233600Z"],
cast(ubyte[])"Action=ListUsers&Version=2010-05-08");
auto sig = makeCRSigV4(r);
assert(sig ==
"3511de7e95d28ecd39e9513b642aee07e54f4941150d8df8bf94b328ef7e55e2");
}
struct SignableRequest
{
string dateString;
string timeStringUTC;
string region;
string service;
CanonicalRequest canonicalRequest;
}
string signableString(SignableRequest r) {
return algorithm ~ "\n" ~
r.dateString ~ "T" ~ r.timeStringUTC ~ "Z\n" ~
r.dateString ~ "/" ~ r.region ~ "/" ~ r.service ~
"/aws4_request\n" ~
makeCRSigV4(r.canonicalRequest);
}
unittest {
string[string] empty;
SignableRequest r;
r.dateString = "20110909";
r.timeStringUTC = "233600";
r.region = "us-east-1";
r.service = "iam";
r.canonicalRequest = CanonicalRequest(
"POST",
"/",
empty,
["content-type": "application/x-www-form-urlencoded;
charset=utf-8",
"host": "iam.amazonaws.com",
"x-amz-date": "20110909T233600Z"],
cast(ubyte[])"Action=ListUsers&Version=2010-05-08");
auto sampleString =
algorithm ~ "\n" ~
"20110909T233600Z\n" ~
Re: How to check if JSONValue of type object has a key?
Am Tue, 06 Oct 2015 21:39:28 +
schrieb Fusxfaranto :
> Additionally, just like associative arrays, if you need to access
> the value, you can get a pointer to it with the in operator (and
> if the key doesn't exist, it will return a null pointer).
>
> const(JSONValue)* p = "key" in root;
> if (p)
> {
> // key exists, do something with p or *p
> }
> else
> {
> // key does not exist
> }
And you could go further and write
if (auto p = "key" in root)
{
// key exists, do something with p or *p
}
else
{
// key does not exist
}
--
Marco
Re: Varargs and default arguments
On 10/6/15 4:27 PM, anonymous wrote:
You can put an expression tuple ("expression AliasSeq"??) there. T.init is
one that always fits T's types. But you could generate one with different
values, too.
void foo(T...)(string str=null, T args = T.init) {
//...
}
void main()
{
foo();
foo("");
What is T in this case? I wondered, and it is an empty expression tuple
(prints out as "()"). Interesting.
Note, this doesn't seem to work on 2.067.
There are other ways to solve this too:
void foo() {return foo(null);}
void foo(T...)(string str, T args) {...}
I find it quite fascinating that in anonymous' solution, the T.init
doesn't ever actually get used!
-Steve
Re: Bug? 0 is less than -10
On Tuesday, 6 October 2015 at 14:55:23 UTC, Adam D. Ruppe wrote:
On Tuesday, 6 October 2015 at 14:46:56 UTC, tcak wrote:
void main(){
size_t dec = 0;
How is it generating "true" for (dec <= -10) ? Is there a
special casting or something?
size_t is unsigned, so the -10 is cast to unsigned too for the
comparison which yields some huge number.
Comparing signed to unsigned is almost always a mistake... but
one D inherited from C.
This is a reason why I prefer to use int instead of size_t
where I can but that might require casts and truncation too.
could we have ssize_t defined in phobos somewhere so your code
ends up being portable ;) (It's trivial to do, obviously).
Re: How to check if JSONValue of type object has a key?
On Tuesday, 6 October 2015 at 20:44:30 UTC, via
Digitalmars-d-learn wrote:
On Tue, Oct 06, 2015 at 08:28:46PM +, Borislav Kosharov via
Digitalmars-d-learn wrote:
JSONValue root = parseJSON(text);
if(root["key"].isNull == false) {
try
if("key" in root) {
// it is there
} else {
// it is not there
}
you can also do
if("key" !in root) {}
Additionally, just like associative arrays, if you need to access
the value, you can get a pointer to it with the in operator (and
if the key doesn't exist, it will return a null pointer).
const(JSONValue)* p = "key" in root;
if (p)
{
// key exists, do something with p or *p
}
else
{
// key does not exist
}
Re: How to check if JSONValue of type object has a key?
On Tue, Oct 06, 2015 at 08:28:46PM +, Borislav Kosharov via
Digitalmars-d-learn wrote:
> JSONValue root = parseJSON(text);
> if(root["key"].isNull == false) {
try
if("key" in root) {
// it is there
} else {
// it is not there
}
you can also do
if("key" !in root) {}
Re: Problem with type cast in if condition
On Tuesday, 6 October 2015 at 20:35:28 UTC, NiRu wrote:
if(is(typeof(value) == User)){
Use `static if` instead of plain `if` here.
Regular if does a runtime branch, so both true and else branches
must compile with the same types.
Static if does a compile time branch, allowing different code to
be compiled based on the condition - meaning types can change too.
Problem with type cast in if condition
Hi there,
I have a problem with the typecast within my if condition, the
dmd2 compiler says he can not cast int to User, but it never
reaches an int type the condition (at most, the else branch).
my try:
struct User {
string name;
}
void printName(T)(T value)
{
if(is(typeof(value) == User)){
User u = cast(User) value;
writeln(u.name);
write("User Type: ");
writeln(value);
} else {
write("Another Type: ");
writeln(value);
}
}
void main(string[] args)
{
User person;
person.name = "Jacub";
printName(362);
printName("have a nice day");
printName(person);
}
without the type cast line I have the following output:
Another Type: 362
Another Type: have a nice day
User Type: User("Jacub")
Instead with type cast "Error: cannot cast expression value of
type int to User"
where is the problem?
Thanks!
How to check if JSONValue of type object has a key?
I'm using std.json for parsing json. I need to check if a
specific string key is in JSONValue.object. The first thing I
tried was:
JSONValue root = parseJSON(text);
if(root["key"].isNull == false) {
//do stuff with root["key"]
}
But that code doesn't work, because calling root["key"] will
throw an exception of key not fount if "key" isn't there.
I need some method `root.contains("key")` method to check if the
object has a key.
Thanks in advance!
Re: Varargs and default arguments
On Tuesday 06 October 2015 22:01, Nick Sabalausky wrote:
> Ok, D-style varargs can accept a parameter length of zero:
>
> ---
> void foo(T...)(T args) {
> //...
> }
> foo();
> foo(t1, t2);
> ---
Terminology fun:
The spec uses the term "D-style variadic function" for something else yet:
`int abc(char c, ...);` -- http://dlang.org/function.html#variadic
Yours is technically a "variadic function template", I guess, i.e., a
function template that's variadic, not a template of a variadic function.
> Is there any way to stick a param with a default value before that?
>
> ---
> void foo(T...)(string str=null, T args=/+what goes here???+/) {
> //...
> }
> foo();
> foo(str);
> foo(str, t1, t2);
> ---
>
> Obviously this can be worked around easily enough by splitting it into
> two overloads ("foo(string str=null)" and "foo(string str, T args)"),
> but is there a way to do it in one?
You can put an expression tuple ("expression AliasSeq"??) there. T.init is
one that always fits T's types. But you could generate one with different
values, too.
void foo(T...)(string str=null, T args = T.init) {
//...
}
void main()
{
foo();
foo("");
foo("", 1, 2);
}
Varargs and default arguments
Ok, D-style varargs can accept a parameter length of zero:
---
void foo(T...)(T args) {
//...
}
foo();
foo(t1, t2);
---
Is there any way to stick a param with a default value before that?
---
void foo(T...)(string str=null, T args=/+what goes here???+/) {
//...
}
foo();
foo(str);
foo(str, t1, t2);
---
Obviously this can be worked around easily enough by splitting it into
two overloads ("foo(string str=null)" and "foo(string str, T args)"),
but is there a way to do it in one?
Re: Linker error with dmd
On Friday, 2 October 2015 at 14:03:08 UTC, John Colvin wrote: On Friday, 2 October 2015 at 09:43:54 UTC, Chris wrote: Why do I get this error msg with dmd 2.067.1 and 2.068.0 in release mode: $ dub --build=release (.data._D65TypeInfo_xC3std5range10interfaces18__T10InputRangeTiZ10InputRange6__initZ+0x10): undefined reference to `_D64TypeInfo_C3std5range10interfaces18__T10InputRangeTiZ10InputRange6__initZ' collect2: error: ld returned 1 exit status --- errorlevel 1 dmd failed with exit code 1. It works fine with the latest version of ldc2. What is it that you are building? An executable. I mainly use a code base that compiles perfectly well in release mode. I couldn't find the reason for this error message, plus, ldc2 has no problem with it.
Re: Bug? 0 is less than -10
On Tuesday, 6 October 2015 at 14:46:56 UTC, tcak wrote:
Maybe I am just too stressed out to see the problem.
[code]
import std.stdio;
void main(){
size_t dec = 0;
writeln( dec, " ", (dec <= -10), " ", (dec >= 10), " ", ((dec
<= -10) || (dec >= 10)) );
}
[/code]
[output]
0 true false true
[/output]
How is it generating "true" for (dec <= -10) ? Is there a
special casting or something?
DMD 2.068.2, Ubuntu 64-bit
If you need to mix signed and unsigned values but want to avoid
this issue, you an use the comparison functions from
std.functional.
http://dlang.org/phobos/std_functional.html#.lessThan
Re: What is the postfix for min long value?
On Tuesday, October 06, 2015 15:16:12 tcak via Digitalmars-d-learn wrote: > While writing max ulong value, I added the "u" postfix. So > compiler accepted it as ulong value (That's my interpretation if > correct on compiler's side). > > writeln( 18_446_744_073_709_551_615u ); > > But when I try to print out minimum value of long, compiler says > Error: signed integer overflow > > writeln( -9_223_372_036_854_775_808 ); > > In case that is the wrong value, I checked it with writeln( > long.min ); already. > > Do I need to put a postfix for that number? I checked > documentation by searching "dlang integer" etc, but couldn't have > found any information/anything about postfix at all. L is the prefix to use, but it looks like there's a compiler bug here, because long l = -9_223_372_036_854_775_807L; compiles and long l = -9_223_372_036_854_775_808L; doesn't, even though that's the same as long.min. long l = -9_223_372_036_854_775_807UL; compiles and does the right thing, though that's a pretty silly thing to have to do. Actually, digging through bugzilla, it looks like it's already been reported: https://issues.dlang.org/show_bug.cgi?id=8929 Though since C has the same problem, it's treated as an enhancement rather than a bug (which seems wrong to me). Apparently, the problem stems from the compiler processing the literal and _then_ applying the sign, and long.max is 9_223_372_036_854_775_807L. Apparently, -2L^^63 will work though. All in all, it's probably not a big deal, since you should probably just being using long.min anyway, but this doesn't seem like particularly good behavior to me. - Jonathan M Davis
Re: What is the postfix for min long value?
On Tuesday 06 October 2015 17:39, Ali Çehreli wrote: > I would expect the following to work: > > writeln( -9_223_372_036_854_775_808L); > > But it doesn't compile: > >Error: signed integer overflow > > It looks like a compiler bug to me. If so, a very embarrassing one. :) https://issues.dlang.org/show_bug.cgi?id=8929
Re: What is the postfix for min long value?
On 10/06/2015 08:16 AM, tcak wrote: > While writing max ulong value, I added the "u" postfix. Better to use U to be consistent with L (see below). > But when I try to print out minimum value of long, compiler says > Error: signed integer overflow > > writeln( -9_223_372_036_854_775_808 ); I would expect the following to work: writeln( -9_223_372_036_854_775_808L); But it doesn't compile: Error: signed integer overflow It looks like a compiler bug to me. If so, a very embarrassing one. :) (You can use UL and LU as well.) > Do I need to put a postfix for that number? I checked documentation by > searching "dlang integer" etc, but couldn't have found any > information/anything about postfix at all. They go by "suffix". The officital documentation: http://dlang.org/lex.html#integerliteral My short mention of them start at the section "The L suffix": http://ddili.org/ders/d.en/literals.html#ix_literals.literal (They were missing in my index section. Adding now...) Ali
What is the postfix for min long value?
While writing max ulong value, I added the "u" postfix. So compiler accepted it as ulong value (That's my interpretation if correct on compiler's side). writeln( 18_446_744_073_709_551_615u ); But when I try to print out minimum value of long, compiler says Error: signed integer overflow writeln( -9_223_372_036_854_775_808 ); In case that is the wrong value, I checked it with writeln( long.min ); already. Do I need to put a postfix for that number? I checked documentation by searching "dlang integer" etc, but couldn't have found any information/anything about postfix at all.
Re: Bug? 0 is less than -10
On Tuesday, 6 October 2015 at 14:46:56 UTC, tcak wrote:
Maybe I am just too stressed out to see the problem.
[code]
import std.stdio;
void main(){
size_t dec = 0;
writeln( dec, " ", (dec <= -10), " ", (dec >= 10), " ", ((dec
<= -10) || (dec >= 10)) );
}
[/code]
[output]
0 true false true
[/output]
How is it generating "true" for (dec <= -10) ? Is there a
special casting or something?
DMD 2.068.2, Ubuntu 64-bit
dec is a size_t. size_t is unsigned. -10 is cast to unsigned for
the comparison, resulting in some huge value.
Re: Bug? 0 is less than -10
On Tuesday, 6 October 2015 at 14:46:56 UTC, tcak wrote:
void main(){
size_t dec = 0;
How is it generating "true" for (dec <= -10) ? Is there a
special casting or something?
size_t is unsigned, so the -10 is cast to unsigned too for the
comparison which yields some huge number.
Comparing signed to unsigned is almost always a mistake... but
one D inherited from C.
This is a reason why I prefer to use int instead of size_t where
I can but that might require casts and truncation too.
Bug? 0 is less than -10
Maybe I am just too stressed out to see the problem.
[code]
import std.stdio;
void main(){
size_t dec = 0;
writeln( dec, " ", (dec <= -10), " ", (dec >= 10), " ", ((dec <=
-10) || (dec >= 10)) );
}
[/code]
[output]
0 true false true
[/output]
How is it generating "true" for (dec <= -10) ? Is there a special
casting or something?
DMD 2.068.2, Ubuntu 64-bit
Re: Concatenation of ubyte[] to char[] works, but assignation doesn't
On Tuesday, October 06, 2015 09:28:27 Marc Schütz via Digitalmars-d-learn wrote:
> I see, this is a new problem introduced by `char + int = char`.
> But at least the following could be disallowed without
> introducing problems:
>
> int a = 'a';
> char b = 32;
Sure, it would be nice, but I rather doubt that Walter would go for it. He
seems to be fully in the camp of folks that think that life is better if
charater types and bool always are treated as integral types - which
unfortunately, creates fun problems like this
void foo(bool b) { writeln("bool"); }
void foo(long l) { writeln("long"); }
foo(1); // prints bool
In this case, adding on overload that takes int fixes the problem, because
integer literals default to int, but in general, it's just stupid IMHO. But
when it was brought up last, Walter didn't think that there was any problem
with it and that it was just fine to require that the int overload be added
to fix it.
> But strictly speaking, we already accept overflow (i.e. loss of
> precision) for ints, so it's a bit inconsistent to disallow it
> for chars.
Overflow is only permitted when doing arithmetic operations (when you really
can't do anything about it except maybe throw an exception, which would be
too expensive to be worth it) or when casting explicitly (in which case,
you're telling the compiler that you don't care). Overflow is never allowed
via implicit conversions.
- Jonathan M Davis
Re: Concatenation of ubyte[] to char[] works, but assignation doesn't
On Tuesday, 6 October 2015 at 09:28:29 UTC, Marc Schütz wrote: I see, this is a new problem introduced by `char + int = char`. But at least the following could be disallowed without introducing problems: int a = 'a'; char b = 32; But strictly speaking, we already accept overflow (i.e. loss of precision) for ints, so it's a bit inconsistent to disallow it for chars. Yes, D does not have overflow, it has modular arithmetics. So the same argument would hold for an enumeration (like character ranges), do you want them to be modular (a circle) or monotonic (a line). Neither is a good fit for unicode. It probably would make most sense to split the unicode universe into multiple typed ranges, some enumerations, some non-enumerations and avoid char altogether.
Re: Concatenation of ubyte[] to char[] works, but assignation doesn't
On Tuesday, 6 October 2015 at 05:38:36 UTC, Jonathan M Davis wrote: Your suggestion only works by assuming that the result will fit in a char, which doesn't fit at all with how coversions are currently done in D. It would allow for narrowing conversions which lost data. And there's no way that Walter would go for that (and I don't think that he should). VRP solves the problem insofar as it can guarantee that the result will fit in the target type and thus reduces the need for casting, but simply assuming that char + int will fit in a char just doesn't work unless we're going to allow narrowing conversions to lose data, which we aren't. If we were to allow the specific conversions that you're suggesting but only when VRP was used, then that could work, though it does make the implicit rules even screwier, becauses it becomes very dependent on how the int that you're trying to assign to a char was generated in the first place (straight assignment wouldn't work, but '0' - 40 would, whereas 'a' + 500 wouldn't, etc.). VRP already makes it a bit funky as it is, though mostly in a straightforward manner. I see, this is a new problem introduced by `char + int = char`. But at least the following could be disallowed without introducing problems: int a = 'a'; char b = 32; But strictly speaking, we already accept overflow (i.e. loss of precision) for ints, so it's a bit inconsistent to disallow it for chars.
Re: Picking specific D compiler with rdmd
--compiler
Re: Picking specific D compiler with rdmd
On Tuesday, 6 October 2015 at 07:16:39 UTC, Nordlöw wrote: I find now flag to rdmd for choosing a specific dmd. Is there none? Doh, there was already: --compiler
Picking specific D compiler with rdmd
I find now flag to rdmd for choosing a specific dmd. Is there none?
Re: std.Algebraic alias this
On Tuesday, 6 October 2015 at 06:37:16 UTC, Nicholas Wilson wrote: On Monday, 5 October 2015 at 11:31:32 UTC, Radu wrote: There is a weird rule on how compiler treats alias this for the N and S types bellow. [...] Please file a bug report. Also do the errors change if you reverse the order in T i.e. alias T = Algebraic!(S,N); ? bug report https://issues.dlang.org/show_bug.cgi?id=15168
