I was reading some of the examples of writing a quine with D, but apparently the language has evolved and they no longer compiled unchanged.

So I tried to program one by myself using strings and std.stdio, but the result seems long and redundant:

import std.stdio;void main(){string s=`import std.stdio;void main(){string s=writefln("%s\x60%s\x60;s",s[0..38],s,s[38..$]);}`;writefln("%s\x60%s\x60;%s",s[0..38],s,s[38..$]);}

Any ideas for a shorter version (preferably without using pointers)?

On Sunday, 15 January 2017 at 19:43:22 UTC, Nestor wrote:
> I was reading some of the examples of writing a quine with D, but apparently the language has evolved and they no longer compiled unchanged.
>
> So I tried to program one by myself using strings and std.stdio, but the result seems long and redundant:
>
> import std.stdio;void main(){string s=`import std.stdio;void main(){string s=writefln("%s\x60%s\x60;s",s[0..38],s,s[38..$]);}`;writefln("%s\x60%s\x60;%s",s[0..38],s,s[38..$]);}
>
> Any ideas for a shorter version (preferably without using pointers)?

Well I just noticed a few problems in the code, I guess quines are a little complex to write.

On Sunday, 15 January 2017 at 21:37:53 UTC, Nestor wrote:
>> Any ideas for a shorter version (preferably without using pointers)?

When compiling with the -main flag, this D program is a quine:

On Sunday, 15 January 2017 at 22:08:47 UTC, pineapple wrote:
> On Sunday, 15 January 2017 at 21:37:53 UTC, Nestor wrote:
>>> Any ideas for a shorter version (preferably without using pointers)?
>
> When compiling with the -main flag, this D program is a quine:

You forgot to include the program... or is this a joke? ;)

On Sunday, 15 January 2017 at 22:35:26 UTC, Nestor wrote:
> You forgot to include the program... or is this a joke? ;)

Neither: the empty program compiles and runs, outputting nothing. Since its empty output matches its empty source file, it technically fits the definition of the quine :)

A quine I came up with a while ago, using q{} string notation:

enum s = q{enum s = q{%s};
void main() {
    import std.stdio;
    writefln(s,s);
}};
void main() {
    import std.stdio;
    writefln(s,s);
}

On Sunday, 15 January 2017 at 19:43:22 UTC, Nestor wrote:
> I was reading some of the examples of writing a quine with D, but apparently the language has evolved and they no longer compiled unchanged.
>
> So I tried to program one by myself using strings and std.stdio, but the result seems long and redundant:
>
> import std.stdio;void main(){string s=`import std.stdio;void main(){string s=writefln("%s\x60%s\x60;s",s[0..38],s,s[38..$]);}`;writefln("%s\x60%s\x60;%s",s[0..38],s,s[38..$]);}
>
> Any ideas for a shorter version (preferably without using pointers)?

I remember on Rosetta to have seen this:

module quine;
import std.stdio;
void main(string[] args)
{
    write(import("quine.d"));
}

compiles with: dmd path/quine.d -Jpath

On Monday, 16 January 2017 at 06:41:50 UTC, Basile B. wrote:
> I remember on Rosetta to have seen this:
>
> module quine;
> import std.stdio;
> void main(string[] args)
> {
>     write(import("quine.d"));
> }
>
> compiles with: dmd path/quine.d -Jpath

Very good! By the way, module name and arguments aren't needed, so:

import std.stdio;void main(){write(import("q.d"));}

compile with: "dmd q -J."

PS. Isn't this approach considered "cheating" in quines? ;)

On Monday, 16 January 2017 at 09:33:23 UTC, Nestor wrote:
> PS. Isn't this approach considered "cheating" in quines? ;)

I'm afraid so - while the empty program has been technically accepted as being a quine (e.g. http://www.ioccc.org/1994/smr.hint) programs which use file io to read their own source have not.

On Monday, 16 January 2017 at 13:11:38 UTC, pineapple wrote:
> On Monday, 16 January 2017 at 09:33:23 UTC, Nestor wrote:
>> PS. Isn't this approach considered "cheating" in quines? ;)
>
> I'm afraid so - while the empty program has been technically accepted as being a quine (e.g. http://www.ioccc.org/1994/smr.hint) programs which use file io to read their own source have not.

But the program doesn't read from IO it's own program. It is a stand alone executable which does no file IO. The compiler on the other hand does IO to inject the file into the program.