Re: stdin.readln line editing and recall with up arrow
On 25/02/2023 6:36 PM, Daren Scot Wilson wrote: stdin.readln() works fine until I, out of habit, use the up arrow to recall an earlier input and the left/right to move around and change a character. How do I get that to work? Not with that module. You can either use GNU readline itself, or Adam's version within arsd.
stdin.readln line editing and recall with up arrow
stdin.readln() works fine until I, out of habit, use the up arrow to recall an earlier input and the left/right to move around and change a character. How do I get that to work?
Re: Template alias parameter: error: need 'this' for ...
On Friday, 24 February 2023 at 15:28:18 UTC, Steven Schveighoffer wrote: On 2/24/23 7:00 AM, Elfstone wrote: Seems like the same bug is still there after ten years. `static` should not affect module-level functions, but also, this code should work without `static`. Reported, not sure if there's a previous bug, it was hard to come up with a good description: https://issues.dlang.org/show_bug.cgi?id=23738 -Steve It was marked duplicate. I read the comments to the previous issue and felt like reading C++ discussions, except C++ is a lot better documented. Anyway surely `__traits(getAttributes, Bar.t)` compiles. The compiler should "need 'this'" when it actually need 'this' - unless there are attributes that can be bound to 'this'.
Re: dub.selections.json & optional dependencies: How's it work?
On Friday, 24 February 2023 at 19:37:41 UTC, Steven Schveighoffer wrote: On 2/24/23 2:01 PM, jmh530 wrote: I'm looking at the dub package format [1] about optional dependencies and it says: "With this set to true, the dependency will only be used if explicitly selected in dub.selections.json. If omitted, this attribute defaults to false." And it occurs to me that I don't know anything about how dub.selections.json works. Let's say you have dependency A, which has an *optional* dependency on B. In your project, if you depend on A, but don't explicitly depend on B, then A will be built without B as a dependency. If you have a dependency on A *and* B, then B's optional dependency will kick in, and participate in the selection of it's version. So for instance, you could depend on B version 1 or higher, and the optional dependency could be on v1.5 or higher, it will select the highest version of 1.5 dub.selections.json only applies to the primary project. So the decision on which versions of which dependencies to use is decided by the whole tree. -Steve Ok this makes sense. So it's all about dependencies downstream. For instance, if I list B as a dependency in my project but never use it in my own project, it will still compile in (so for instance if A's functionality differs depending on if B is included, then I will get that functionality even if I don't use B directly in my project).
Re: dub.selections.json & optional dependencies: How's it work?
On 2/24/23 2:01 PM, jmh530 wrote: I'm looking at the dub package format [1] about optional dependencies and it says: "With this set to true, the dependency will only be used if explicitly selected in dub.selections.json. If omitted, this attribute defaults to false." And it occurs to me that I don't know anything about how dub.selections.json works. Let's say you have dependency A, which has an *optional* dependency on B. In your project, if you depend on A, but don't explicitly depend on B, then A will be built without B as a dependency. If you have a dependency on A *and* B, then B's optional dependency will kick in, and participate in the selection of it's version. So for instance, you could depend on B version 1 or higher, and the optional dependency could be on v1.5 or higher, it will select the highest version of 1.5 dub.selections.json only applies to the primary project. So the decision on which versions of which dependencies to use is decided by the whole tree. -Steve
dub.selections.json & optional dependencies: How's it work?
I'm looking at the dub package format [1] about optional dependencies and it says: "With this set to true, the dependency will only be used if explicitly selected in dub.selections.json. If omitted, this attribute defaults to false." And it occurs to me that I don't know anything about how dub.selections.json works. I would think dub optional dependencies work such that if there are no functions being called/compiled that import an optional dependency, then the dependency wouldn't be included. How is it different from `dmd -i`? The dub.selections.json in some of my projects look like a listing of the dependencies and their versions. Above should imply that the optional dependency would only get included there if the import is actually used somewhere in the project. Is that correct? [1] https://dub.pm/package-format-json.html
Re: Template alias parameter: error: need 'this' for ...
On Friday, 24 February 2023 at 14:22:17 UTC, user1234 wrote:
you can break using `goto`, restore `static` everywhere, and
using local introspection determine whether the result exists.
```d
struct Bar
{
@("hello") int t;
}
static bool hasAttribute(alias F, T)()
{
static foreach (a; __traits(getAttributes, F))
{
static if (is(typeof(a) : T))
{
enum result = true;
goto L0;
}
}
L0:
static if (is(typeof(result)))
return result;
else
return false;
}
void main()
{
import std.stdio;
writeln(hasAttribute!(Bar.t, string));
}
```
Unfortunately there is a serious bug in this code. Take a look at
what happens when you try it with this `struct Bar`:
```d
struct Bar
{
@("hello") @("goodbye") int t;
}
```
Re: Template alias parameter: error: need 'this' for ...
On 2/24/23 7:00 AM, Elfstone wrote: Seems like the same bug is still there after ten years. `static` should not affect module-level functions, but also, this code should work without `static`. Reported, not sure if there's a previous bug, it was hard to come up with a good description: https://issues.dlang.org/show_bug.cgi?id=23738 -Steve
Re: Template alias parameter: error: need 'this' for ...
On Friday, 24 February 2023 at 12:00:41 UTC, Elfstone wrote:
Seems like the same bug is still there after ten years.
```d
struct Bar
{
@("hello") int t;
}
static bool hasAttribute(alias F, T)()
{
bool result = false;
foreach (a; __traits(getAttributes, F))
{
static if (is(typeof(a) : T))
{
result = true; // couldn't simply return true, 'cause the
compiler complains about "unreachable code".
}
}
return result;
}
void main()
{
import std.stdio;
writeln(hasAttribute!(Bar.t, string));
}
```
you can break using `goto`, restore `static` everywhere, and
using local introspection determine whether the result exists.
```d
struct Bar
{
@("hello") int t;
}
static bool hasAttribute(alias F, T)()
{
static foreach (a; __traits(getAttributes, F))
{
static if (is(typeof(a) : T))
{
enum result = true;
goto L0;
}
}
L0:
static if (is(typeof(result)))
return result;
else
return false;
}
void main()
{
import std.stdio;
writeln(hasAttribute!(Bar.t, string));
}
```
Template alias parameter: error: need 'this' for ...
https://forum.dlang.org/post/imnannjdgtjnlzevh...@forum.dlang.org
On Saturday, 24 August 2013 at 11:47:43 UTC, Matej Nanut wrote:
On Friday, 23 August 2013 at 22:54:33 UTC, Jonathan M Davis
wrote:
Because without static it's a member variable, which means
that you have to
have a constructed object to access it (since it's part of the
object). When
you declare a variable in a class or struct static, then
there's only one for
the entire class or struct, so it can be accessed without an
object. And when
you do StructName.var or ClassName.var your accessing the
variable via the
struct or class rather than an object, so the variable must be
static.
- Jonathan M Davis
But I declared the template static, not the variable.
Is there a better way to pass a ‘member get’ expression to a
template?
I need this for calling ‘.offsetof’ on it, and for checking if
the member's parent is a certain struct type.
Seems like the same bug is still there after ten years.
struct Bar
{
@("hello") int t;
}
static bool hasAttribute(alias F, T)()
{
bool result = false;
foreach (a; __traits(getAttributes, F))
{
static if (is(typeof(a) : T))
{
result = true; // couldn't simply return true, 'cause the
compiler complains about "unreachable code".
}
}
return result;
}
void main()
{
import std.stdio;
writeln(hasAttribute!(Bar.t, string));
}
Re: dub creates unrunnable binary in "build" dir
On Thursday, 23 February 2023 at 12:28:35 UTC, Richard (Rikki) Andrew Cattermole wrote: On 24/02/2023 1:10 AM, tastyminer...@gmail.com wrote: The symbol exists if I understood correctly. -imports shows you the imports of the binary, not the exports. So no it does not exist (probably came from libc). https://keith.github.io/xcode-man-pages/dyld_info.1.html My guess is something changed some place else. Such as XCode or tcl. Yes, you're correct. I managed to resolve it. So "_memcmp" was missing and it is part of the libc library. I remember that MacPorts asked me to reclaim some space by removing the deps of inactive ports. When agreed, it removed almost complete port library including many libs used for compilation of other ports. I managed to restore most of them but looks like glibc2 was still missing. After installing it and libgcc with deps, the project compiled without issues.
