better explanation of quine with macros

This commit is contained in:
Hugo LAMY
2025-01-04 11:26:26 +01:00
parent e645122f15
commit acd99e3e30

120
notes.md
View File

@@ -200,12 +200,7 @@ int main()
}
```
**in one line :**
```
int main(){ char *quine = THIS_LINE_&_THE_LINES_AROUND; printf(quine); return 0; }
```
**whole code idea :**
**with macros :**
```
#include <stdio.h>
#define MAIN() int main() { char *quine = "BEFORE" "THIS_MACRO_ITSELF" "AFTER"; printf(quine); return 0; }
@@ -219,21 +214,28 @@ MAIN()
```
#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; }
#define MAIN(s) \
int main() \
{ \
char *quine = "#include <stdio.h>\n#define MAIN(s) " \
s \
"\n\nMAIN(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 :**
**expands to :**
```
int main()
{
char *quine = "#include <stdio.h>\n#define MAIN(s) "s "\n\nMAIN(MAIN(s))";
printf(quine);
return 0;
char *quine = "#include <stdio.h>\n#define MAIN(s) "
s
"\n\nMAIN(s)\n";
printf(quine);
return 0;
}
```
@@ -245,21 +247,34 @@ int 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; }
#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 :**
**expands to :**
```
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;
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))\n";
printf(quine);
return 0;
}
"\n\nMAIN(MAIN(s))\n";
printf(quine);
return 0;
}
```
@@ -276,32 +291,45 @@ int main()
#define MAIN(s) content s content
MAIN(str(MAIN(s)))
/* EQUIVALENT */
/* EQUIVALENT TO : */
#define MAIN(s) content s content
MAIN((MAIN(s)))
```
**we can use this extra step to stringify the content :**
**we can use this extra step to stringify the content with #s :**
```
#define str(s) #s
#define MAIN(s) content s content
MAIN(str(MAIN(s)))
```
**example :**
```
#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; }
#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 :**
**expands to :**
```
int main()
{
char *quine = "#include <stdio.h>\n#define MAIN(s) ""MAIN(s)""\n\nMAIN(str(MAIN(s)))";
printf(quine);
return 0;
char *quine = "#include <stdio.h>\n#define str(s) #s\n#define MAIN(s) "
"MAIN(s)"
"\n\nMAIN(str(MAIN(s)))\n";
printf(quine);
return 0;
}
```
@@ -315,24 +343,28 @@ int main()
#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; }
#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 :**
**expands to :**
```
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;
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;
}
```