- [interactions between MACRO and comments](https://gcc.gnu.org/onlinedocs/cpp/Stringizing.html#:~:text=the%20stringized%20result.-,Comments,-are%20replaced%20by)
- [preprocessor strip comments before exapnding macros](https://stackoverflow.com/questions/1510869/does-the-c-preprocessor-strip-comments-or-expand-macros-first)
- [create an include with a macro OR NOT](https://stackoverflow.com/questions/1135822/escaping-a-symbol-in-a-define-macro)

---

## make rules :

- make in root will make all projects
- make in each project will compile this project
- make diff : compile if necessary, and run the program then compare the output
- make concat : create the concatenated version, finale version, of the quine

## folder structure

> Each programs will have to be coded in C and in Assembly, and respectivly in a folder named C and ASM, each folders containing its own Makefile with the usual rules.

```
dr_quine/
| C/
| | Colleen.c
| | Grace.c
| | Sully.c
| | Makefile
| | ...
| ASM/
| | Colleen.asm
| | Grace.asm
| | Sully.asm
| | Makefile
| | ...
```


---


## Grace
---

#### 1 : a string containing itself, almost
---

```
#define xstr(s) str(s)
#define str(s) char *quine = #s ; printf(quine);

xstr(str())
```

**expansions :**
-> `xstr ( char *quine = "" ; printf(quine); )`
-> `char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine);`

**problem :** `\"\"` instead of `#s` :
-> `char *quine = "char *quine = #s ; printf(quine);" ; printf(quine);`


#### 1.2 : the output, first try
---

```
#include <stdio.h>
#define MAIN(s) int main(){ s return 0; }
#define xstr(s) str(s)
#define str(s) char *quine = #s ; printf(quine);

MAIN(xstr(str()))
```

**expansions :**
-> `MAIN( xstr( char *quine = "" ; printf(quine); ))`
-> `MAIN( char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine); )`
-> `int main(){ char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine); return 0; }`

**exploded view :**
```
int main(){
	char *quine = "char *quine = \"\" ; printf(quine);" ;
	printf(quine);
	return 0;
}
```

**output :**
```
char *quine = "" ; printf(quine);
```

**problem 1 :** missing the main function around the content
**problem 2 :** quine does not contain itself, but an empty string


#### 1.3 : the output, second try
---

```
#include <stdio.h>
#define MAIN(s) int main(){ s return 0; }
#define xstr(s) str(s)
#define str(s) char *quine = #s ; printf(quine);

MAIN(xstr(MAIN(xstr(str()))))
```

**expansions :**
-> `MAIN( xstr( MAIN( xstr( char *quine = "" ; printf(quine); ))))`
-> `MAIN( xstr( MAIN( char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine); )))`
-> `MAIN( xstr( int main(){ char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine); return 0; } ))`
-> `MAIN( char *quine = "int main(){ char *quine = \"char *quine = \\\"\\\" ; printf(quine);\" ; printf(quine); return 0; }" ; printf(quine); )`
-> `int main(){ char *quine = "int main(){ char *quine = \"char *quine = \\\"\\\" ; printf(quine);\" ; printf(quine); return 0; }" ; printf(quine); return 0; }`

**exploded view :**
```
int main()
{
	char *quine =
	"
		int main()
		{
			char *quine = \"char *quine = \\\"\\\" ; printf(quine);\" ;
			printf(quine);
			return 0;
		}
	";

	printf(quine);
	return 0;
}
```

**output :**
```
int main(){ char *quine = "char *quine = \"\" ; printf(quine);" ; printf(quine); return 0; }%                                
```

**exploded view :**
```
int main()
{
	char *quine = "char *quine = \"\" ; printf(quine);";
	printf(quine);
	return 0;
}
```

**problem :** this new program will only print :
`char *quine = "" ; printf(quine);`



#### 1.3 : the output, third try
---

```
#include <stdio.h>
#define MAIN(s) int main(){ s return 0; }
#define xstr(s) str(s)
#define str(s) char *quine = #s ; printf(quine);

MAIN(xstr(MAIN(xstr(MAIN(xstr())))))
```
**output :**
`int main(){ char *quine = "int main(){ char *quine = \"\" ; printf(quine); return 0; }" ; printf(quine); return 0; }`

**exploded view :**
```
int main()
{
	char *quine =
	"
		int main()
		{
			char *quine = \"\";
			printf(quine);
			return 0;
		}
	";
	printf(quine);
	return 0;
}
```

**problem :** we cannot gon on like this, there will always be one level missing
**idea :** changing the inner `char* quine =` content to '%s' and printing `printf(quine, quine)`




#### 2 : second approach
---

**a quine could be this structure basically :**
```
int main()
{
	char *quine = THE_WHOLE_PROGRAM;
	printf(quine);
	return 0;
}
```

**in one line :**
```
int main(){ char *quine = THIS_LINE_&_THE_LINES_AROUND; printf(quine); return 0; }
```

**whole code idea :**
```
#include <stdio.h>
#define MAIN() int main() { char *quine = "BEFORE" "THIS_MACRO_ITSELF" "AFTER"; printf(quine); return 0; }

MAIN()
```


#### 2.1 : let's try it
---

```
#include <stdio.h>
#define MAIN(s) int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "s"\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }

MAIN(s)
```

**expansions :**
-> `int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "s "\n\nMAIN(MAIN(s))\n"; printf(quine); return 0; }`

**exploded view :**
```
int main()
{
	char *quine = "#include <stdio.h>\n#define MAIN(s) "s "\n\nMAIN(MAIN(s))";
	printf(quine);
	return 0;
}
```

**problem :** the `char *quine` string should contain a copy of the whole code in place of "s"


#### 2.2 : second try, macro calling itself : MAIN(MAIN)
---

```
#include <stdio.h>
#define MAIN(s) int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "s"\n\nMAIN(MAIN(s))\n"; printf(quine); return 0; }

MAIN(MAIN(s))
```

**expansions :**
-> `int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "s "\n\nMAIN(MAIN(s))"; printf(quine); return 0; }"\n\nMAIN(MAIN(s))\n"; printf(quine); return 0; }`

**exploded view :**
```
int main()
{
	char *quine = "#include <stdio.h>\n#define MAIN(s) "int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) "s "\n\nMAIN(MAIN(s))"; printf(quine); return 0; }"\n\nMAIN(MAIN(s))\n";
	printf(quine);
	return 0;
}
```

**problem :** almost there, but the content of the string quine should be a litteral string instead of code



#### 2.3 : lets stringify the content of the inner MAIN
---

**the previous can be written with an extra step :**
```
#define str(s) s
#define MAIN(s) content s content
MAIN(str(MAIN(s)))

/* EQUIVALENT */

#define MAIN(s) content s content
MAIN((MAIN(s)))
```

**we can use this extra step to stringify the content :**
```
#include <stdio.h>
#define str(s) #s
#define MAIN(s) int main() { char *quine = "#include <stdio.h>\n#define str(s) #s\n#define MAIN(s) "s"\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }

MAIN(str(MAIN(s)))
```

**expansions :**
-> `int main() { char *quine = "#include <stdio.h>\n#define MAIN(s) ""MAIN(s)""\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }`


**exploded view :**
```
int main()
{
	char *quine = "#include <stdio.h>\n#define MAIN(s) ""MAIN(s)""\n\nMAIN(str(MAIN(s)))";
	printf(quine);
	return 0;
}
```

**problem :** oops, it stringified the parameter name, not it's expanded version, see https://gcc.gnu.org/onlinedocs/cpp/Stringizing.html


#### 2.4 : working stringification
---

```
#include <stdio.h>
#define xstr(s) #s
#define str(s) xstr(s)
#define MAIN(s) int main() { char *quine = "#include <stdio.h>\n#define xstr(s) #s\n#define str(s) xstr(s)\n#define MAIN(s) "s"\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }

MAIN(str(MAIN(s)))
```

**expansions :**
-> `int main() { char *quine = "#include <stdio.h>\n#define xstr(s) #s\n#define str(s) xstr(s)\n#define MAIN(s) ""int main() { char *quine = \"#include <stdio.h>\\n#define xstr(s) #s\\n#define str(s) xstr(s)\\n#define MAIN(s) \"s\"\\n\\nMAIN(str(MAIN(s)))\\n\"; printf(quine); return 0; }""\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }`

**exploded view :**
```
int main()
{
	char *quine =
		"#include <stdio.h>\n#define xstr(s) #s\n#define str(s) xstr(s)\n#define MAIN(s) "
		"int main() { char *quine = \"#include <stdio.h>\\n#define xstr(s) #s\\n#define str(s) xstr(s)\\n#define MAIN(s) \"s\"\\n\\nMAIN(str(MAIN(s)))\\n\"; printf(quine); return 0; }"
		"\n\nMAIN(str(MAIN(s)))\n";
	printf(quine);
	return 0;
}
```

**output :**
```
#include <stdio.h>
#define xstr(s) #s
#define str(s) xstr(s)
#define MAIN(s) int main() { char *quine = "#include <stdio.h>\n#define xstr(s) #s\n#define str(s) xstr(s)\n#define MAIN(s) "s"\n\nMAIN(str(MAIN(s)))\n"; printf(quine); return 0; }

MAIN(str(MAIN(s)))
```

**victory ;)**