Re: Writing own source disk

On 04/06/2024 14:40, Ben Bacarisse wrote:

Malcolm McLean <malcolm.arthur.mclean@gmail.com> writes:
 

On 03/06/2024 13:11, Ben Bacarisse wrote:

Malcolm McLean <malcolm.arthur.mclean@gmail.com> writes:
>

On 02/06/2024 23:17, Ben Bacarisse wrote:

Malcolm McLean <malcolm.arthur.mclean@gmail.com> writes:
>

Writing a prgram which writes its own source to standard output is a
standard programming problem. It's called a quine.

A quine must also not process any input.
>

And I have achieved a
quine. But a serious quine. Not contrived special purpose code, but serious
codde which can be used to package up source for real.

You XML-producing program may be very useful, but it's not really a
quine, serious or otherwise.
>

And it's completely
portable ANSI C. So of course it can't write output to disk - that is
impossible to achive portably. Instead it writes its own source to standard
output using a simle XML format called FileSystem, which represents the
source tree.

That sounds as if the program reads input (but it's not explicitly
stated) as well as not producing the program text but some XML
representation of the program text.  That would make it not a quine for
two reasons.
How do you process a source tree in completely portable ANSI C?

>

The FileSystem XML fie is embedded with the program. It is a genuine
quine. Compile it and see.

No need; I'll take your word for it.
>

It's also a very superior quine, and it spits out images and binaries.

If it's a quine (and I don't doubt you) then is spits out its own source
code.  That can, of course, include source code encodings of images.
I'm not sure why you consider that superior, but that is, after all, a
rather subjective assessment.
>

It's not therortically interesting from a computer science perspective.
You can encode images as source.
>
But from a practical point of view, yes my quine is  massively
powerful. Most graphical programs do have images as source. And they just
get zipped up into the FileSystem XML file. So any binary data can be
included. Easily, Using exactly the same system.

 I'm not getting it.  Why do I want a quine in connection to a graphical
program?  I want a way to include everything in the distribution, but
we've had that for ages.  Why is having a program that outputs something
you already have (by defintion!) of any use?
 

Because you've got the binary, but not the source. And whilst it is a quine, of course it is only a quine when you pass it the -quine option. Otherwise it is Space Invaders. But if you nedd to recompile the program for a new target, -quine spits out the source.
BabyXFS quines are serious quines, they have a real purpose.
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