1:
$cppawk '
#include <narg.h>
BEGIN { print narg(x), narg(x, y), narg(x, y, z), narg(x, y, z, w) }'
:
1 2 3 4
--
2:
$cppawk '
#include <narg.h>
BEGIN { print narg(a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a,a) }'
:
32
--
3:
$cppawk '
#include <narg.h>
BEGIN { print narg(1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1) }'
:
ERR
--
4:
$cppawk '
#include <narg.h>
#define first(x) x
#define rest(prev, x) prev : x
#define colonize(...) [varexpand(first, rest, __VA_ARGS__)]
#define str(x) #x
#define xstr(x) str(x)
#define scolonize(...) xstr(colonize(__VA_ARGS__))
BEGIN { print scolonize(1), scolonize(1,2), scolonize(1, 2, 3) }'
:
[1] [1 : 2] [1 : 2 : 3]
--
5:
$cppawk '
#include <narg.h>
#define str(x) #x
#define xstr(x) str(x)
#define srev(...) xstr((revarg(__VA_ARGS__)))
BEGIN { print srev(1), srev(1,2), srev(1, 2, 3) }'
:
(1) (2, 1) (3, 2, 1)
--
5:
$cppawk '
#include <narg.h>
#define first(x) x
#define rest(prev, x) prev : x
#define colonize(...) [varexpand(first, rest, __VA_ARGS__)]
#define str(x) #x
#define xstr(x) str(x)
#define scolonize(...) xstr(colonize(__VA_ARGS__))
#define scol(x, rest) scolonize(x, splice(rest))
BEGIN { print scol(1, (2, 3)) }'
:
[1 : 2 : 3]
--
6:
x=2
args=1
revargs=1
while [ $x -lt 33 ] ; do
  args="$args, $x"
  revargs="$x $revargs"
  [ "$($cppawk "#include <narg.h>
                BEGIN { print revarg($args) }")" = "$revargs" ] || exit 1
  x=$((x + 1))
done
echo okay
:
okay
--
7:
$cppawk '
#include <narg.h>
#define first(x, i) x ## i
#define rest(prev, x, i) prev : x ## i
#define colonize(...) [variexpand(first, rest, __VA_ARGS__)]
#define str(x) #x
#define xstr(x) str(x)
#define scolonize(...) xstr(colonize(__VA_ARGS__))
BEGIN { print scolonize(a), scolonize(a, b), scolonize(a, b, c) }'
:
[a1] [a1 : b2] [a1 : b2 : c3]
--
7:
$cppawk '
#include <narg.h>
#define first(x, i, a) a-x ## i
#define rest(prev, x, i, a) prev : a-x ## i
#define colonize(a, ...) [variaexpand(first, rest, a, __VA_ARGS__)]
#define str(x) #x
#define xstr(x) str(x)
#define scolonize(...) xstr(colonize(__VA_ARGS__))
BEGIN { print scolonize(m, a), scolonize(n, a, b), scolonize(p, a, b, c) }'
:
[m-a1] [n-a1 : n-b2] [p-a1 : p-b2 : p-c3]