Re: How to make a generic function to take a class or struct by reference?
On Sunday, 27 March 2022 at 16:27:44 UTC, JN wrote:
I would like to have only one definition of getX if possible,
because they both are doing the same thing. I can't remove the
ref one, because without a ref it will pass the struct as a
temporary and compiler won't like that.
```d
import std.stdio;
struct Foo
{
int x;
void doStuff()
{
*getX(this) = 5;
}
}
class Bar
{
int x;
void doStuff()
{
*getX(this) = 5;
}
}
int* getX(T)(ref T t)
{
return &t.x;
}
int* getX(T)(T t)
{
return &t.x;
}
void main()
{
Foo foo;
Bar bar = new Bar();
foo.doStuff();
bar.doStuff();
assert(foo.x == 5);
assert(bar.x == 5);
}
```
Try this:
```d
int* getX(T)(return auto ref T t){
static if(is(T == class))
return &t.x;
else static if(is(T == struct) && __traits(isRef, t))
return &t.x;
else
static assert(0, "no impl " ~ T.stringof);
}
```
or:
```d
int* getX(T)(return auto ref T t)
if(is(T == class) || (is(T == struct) && __traits(isRef, t))){
return &t.x;
}
```
Re: Windows Msys terminal not flushing on newlines
On Sunday, 27 March 2022 at 18:09:30 UTC, Adam D Ruppe wrote: Normally the IOLBF thing does help there - that means line buffering - but my recommentation is to explicitly call `stdout.flush()` any time it is important in your code. Then you aren't depending on the relatively hidden config value. All right, thanks.
Re: Windows Msys terminal not flushing on newlines
Don't know if this is OT here. On Sunday, 27 March 2022 at 18:09:30 UTC, Adam D Ruppe wrote: If the C library thinks it is talking to a pipe, it will switch to block buffering instead of line buffering. It must just think msys is a pipe (since it probably is under the hood). while compiling a project with make -j6 I see this: [...] decimal/decimal.d(13080): decimal/decimal.d(13080): Deprecation: Deprecation: UUssagea goef otfh et h`e `bodbyody` k`e ykweoyrwdo rids idse pdreepcraetceadt.e dU.s eU s`e `dodo` i`n sitnesatde.a d. decimal/decimal.d(13217): decimal/decimal.d(13217): Deprecation: Deprecation: UUssaaggee ooff tthhee ``bbooddyy`` kkeeyywwoorrdd iiss ddeepprreeccaatteedd.. UUssee ``ddoo`` iinnsstteeaadd.. decimal/decimal.d(13239): Deprecation: decimal/decimal.d(13239): UDeprecation: sageU soafg et hoef `the b`odybo`d ykey`w okredy wiosr dd eipsr edceaptreedc.a tUesde. `Use d`o`d oins`t eiands.t ead. decimal/decimal.d(13327): decimal/decimal.d(13327): Deprecation: Deprecation: UUssaaggee ooff tthhee ``bbooddyy`` kkeeyywwoorrdd iiss ddeepprreeccaatteedd.. UUssee ``ddoo`` iinnsstteeaadd.. The write calls are mostly unbuffered as strace reveals: 29680 write(2, "\33[1m", 4) = 4 29680 write(2, "decimal/decimal.d(471): ", 24) = 24 29680 write(2, "\33[1;36m", 7) = 7 29680 write(2, "Deprecation: ", 13) = 13 29680 write(2, "\33[m", 3) = 3 29680 write(2, "U", 1) = 1 29680 write(2, "s", 1) = 1 29680 write(2, "a", 1) = 1 29680 write(2, "g", 1) = 1 29680 write(2, "e", 1) = 1 29680 write(2, " ", 1) = 1 29680 write(2, "o", 1) = 1 29680 write(2, "f", 1) = 1 29680 write(2, " ", 1) = 1 29680 write(2, "t", 1) = 1 29680 write(2, "h", 1) = 1 29680 write(2, "e", 1) = 1 29680 write(2, " ", 1) = 1 Normally the IOLBF thing does help there - that means line buffering - but my recommentation is to explicitly call `stdout.flush()` any time it is important in your code. Then you aren't depending on the relatively hidden config value. Shall I file an issue for this?
Re: How to make a generic function to take a class or struct by reference?
On 3/27/22 12:27 PM, JN wrote:
int* getX(T)(T t)
{
return &t.x;
}
Remove this one. It's a bad idea. It probably won't compile, but if it
does, you will be using corrupted memory.
-Steve
Re: Windows Msys terminal not flushing on newlines
On Sunday, 27 March 2022 at 17:46:54 UTC, Anonymouse wrote: I installed Git for Windows which comes with the Msys terminal, and I noticed writeln lines aren't being flushed on linebreaks If the C library thinks it is talking to a pipe, it will switch to block buffering instead of line buffering. It must just think msys is a pipe (since it probably is under the hood). Normally the IOLBF thing does help there - that means line buffering - but my recommentation is to explicitly call `stdout.flush()` any time it is important in your code. Then you aren't depending on the relatively hidden config value.
Windows Msys terminal not flushing on newlines
I installed Git for Windows which comes with the Msys terminal, and I noticed writeln lines aren't being flushed on linebreaks. I had this a long time ago and thought I fixed it with the following, but I guess I never confirmed that it actually worked. I'm not sure where I copied it from, a TWiD perhaps? ```d import std.stdio : stdout; import core.stdc.stdio : _IOLBF; stdout.setvbuf(4096, _IOLBF); // arbitrary number ``` Is this not the right way to go about things? At least for Msys it seemingly does nothing.
Re: How to make a generic function to take a class or struct by reference?
Auto ref?
```D
int* getX(T)(auto ref T t)
{
...
```
How to make a generic function to take a class or struct by reference?
I would like to have only one definition of getX if possible,
because they both are doing the same thing. I can't remove the
ref one, because without a ref it will pass the struct as a
temporary and compiler won't like that.
```d
import std.stdio;
struct Foo
{
int x;
void doStuff()
{
*getX(this) = 5;
}
}
class Bar
{
int x;
void doStuff()
{
*getX(this) = 5;
}
}
int* getX(T)(ref T t)
{
return &t.x;
}
int* getX(T)(T t)
{
return &t.x;
}
void main()
{
Foo foo;
Bar bar = new Bar();
foo.doStuff();
bar.doStuff();
assert(foo.x == 5);
assert(bar.x == 5);
}
```
Re: Help needed to learn typeof(return)
On Sunday, 27 March 2022 at 01:11:02 UTC, Steven Schveighoffer
wrote:
Not sure what the question here is,
Thanks for the reply. Actually, my problem was this, I forgot the
presence of `LargerOf!(A, B)` template function in that chapter.
When I see it in a function, I thought where is the
implementation of this function ? But later I found it.
And yes, you can get into paradoxical problems like:
```d
auto foo()
{
typeof(return) x;
return x;
}
```
which will not compile.
Yeah, I got the point. In fact, after reading the `Template`
chapter in that book, I am amazed. There are lot of possibilities
in D templates.
Re: Example of Windows SSL with Secure Channel?
On Monday, 21 March 2022 at 17:30:31 UTC, Marcone wrote: I hope one day the creators of the D programming language will implement std.socket.ssl in the Phobos library. I have to agree. For those just getting to grips with D there are some things in the library that just make using them much more difficult than they ought to be, or altogether impossible.
