*	This looks surprising but I do not mind.
**	Hmm... are you sure this compiles?
***	Is it bitrot on on your disk or did you really write that?
****	This belongs to hell, do you belong to hell?
*****	Your soul is cursed, be damned in D00M!

*	assert(!"not reachable");

*	#define ArgvLen(...) sizeof((char[]){ __VA_ARGS__ })

*	#define F(x) { #x, &cmd_##x }
	FnMap map[] = { F(help), F(list), F(add), F(del) };

*	return 0
	|| parse_command_name(&buffer, &cmd)
	|| parse_int_spec(&buffer, &intspec)
	|| pasre_argument_list(&buffer, &arglist)
	|| parse_extra_flags(&buffer, &flags)
	? -1 : 0;

*	#define C 'C',(int)
	#define B 'B',(i64)
	#define D 'D',(i64)
	#define O 'O',(i64)
	#define X 'X',(i64)
	#define E 'E'
	#define S 'S',
	myprint("hello %\n", S"john");

*	#define kHz (1000UL)
	#define MHz (1000UL*kHz)

*	#define KB (1024UL)
	#define MB (1024UL*KB)
	#define GB (1024UL*MB)

*	#define KB (1000UL)
	#define MB (1000UL*KB)
	#define GB (1000UL*MB)

*	#define INFO "a tool to poke around"
	#define AUTHOR "The Dude <thedude@example.org>"
	/* but actually never used in the program */

*	#define Len(x) (sizeof(x) / sizeof(*x))
	#define Min(x, y) ((x) < (y) ? (x) : (y))
	#define Max(x, y) ((x) > (y) ? (x) : (y))
	#define Abs(x) ((x) > 0 ? (x) : -(x))
	#define Sign(x) ((x) > 0 ? 1 : (x) < 0 ? -1 : 0)

*	/* avoids integer overlow */
	#define Dist(x, y) ((x) > (y) ? (x) - (y) : (y) - (x))
	#define Direc(x, y) ((x) < (y) ? 1 : (x) > (y) ? -1 : 0)

*	#define Bit(arr, i) ((arr)[(i) / sizeof(arr) * 8] & 1<<((i) % (sizeof(arr)*8)))

*	enum { B00000000, B00000001, B00000010, B00000011, [...] };

*	#define tostr(n) _tostr((char[50]){ 0 }, 50, n)

*	# cross compiling for multiple targets on a same project
	$ cat arm-none-eabi/Makefile
	O = arm-none-eabi.o
	OBJ = ../main.$O
	all: main.elf
	.SUFFIXES: .$O
	.c.$O:
		arm-none-eabi-gcc ${CFLAGS} -c -o $@ $<
	main.elf: ${OBJ}
		arm-none-eabi-gcc ${LDFLAGS} -o $@ ${OBJ}
	$ ls -P
	./arm-none-eabi/
	./riscv64-unknown-elf/
	./xtensa-esp32-elf/
	./main.arm-none-eabi.o
	./main.xtensa-esp32-elf.o
	./main.riscv64-unknown-elf.o
	./main.c