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/* Testing compound literals */
#include <stdio.h>
struct point { int x, y; };
struct line { struct point from, to; };
void printpoint (struct point p)
{
printf("{x = %d, y = %d}\n", p.x, p.y);
}
void printpointref (struct point * p)
{
printf("{x = %d, y = %d}\n", p->x, p->y);
}
void printline (struct line l)
{
printf("{from = {x = %d, y = %d}, to = {x = %d, y = %d}\n",
l.from.x, l.from.y, l.to.x, l.to.y);
}
static inline struct point diff(struct point a, struct point b)
{
return (struct point){ b.x - a.x, b.y - a.y };
}
/* H&S section 7.4.5 */
char * temp1 = (char []) {"/temp/XXXXXX"};
char * temp2 = "/temp/XXXXXX";
int pow2(int n)
{
if (n >= 0 && n <= 7)
return (const int []) {1,2,4,8,16,32,64,128} [n];
else
return -1;
}
void test1(int n)
{
printf("temp1 = \"%s\"\n", temp1);
printf("temp2 = \"%s\"\n", temp2);
temp1[6] = '!';
printf("mutated temp1 = \"%s\"\n", temp1);
printpoint((struct point){.x=12, .y=n+3});
printpointref(&(struct point){n,-n});
printline((struct line){n,n+1,n+2,n+3});
printline((struct line){.from = (struct point){n-3,n-2},
.to = (struct point){n-1,n}});
printpoint(diff((struct point){n,n}, (struct point){1,1}));
int * ptrs[5];
int i = 0;
again:
ptrs[i] = (int [1]){i};
if (++i < 5) goto again;
printf("ptrs contains %d %d %d %d %d\n",
*(ptrs[0]), *(ptrs[1]), *(ptrs[2]), *(ptrs[3]),*(ptrs[4]));
i = 0;
ptrs[0] = (int [1]){i++};
ptrs[1] = (int [1]){i++};
ptrs[2] = (int [1]){i++};
ptrs[3] = (int [1]){i++};
ptrs[4] = (int [1]){i++};
printf("ptrs contains %d %d %d %d %d\n",
*(ptrs[0]), *(ptrs[1]), *(ptrs[2]), *(ptrs[3]),*(ptrs[4]));
}
/* Examples from GCC's manual */
struct foo { int a; char b[2]; } structure;
char **foo = (char *[]) { "x", "y", "z" };
static struct foo x = (struct foo) {1, 'a', 'b'};
// Dubious examples: GCC refuses them, Clang warns.
// static int y[] = (int []) {1, 2, 3};
// static int z[] = (int [3]) {1};
void test2(int n)
{
structure = (struct foo) {n, 'a', 0};
printf("structure = {a = %d, b = \"%s\"}\n", structure.a, structure.b);
printf("foo = { \"%s\", \"%s\", \"%s\" }\n", foo[0], foo[1], foo[2]);
printf("x = {a = %d, b[0] = '%c', b[1] = '%c'}\n", x.a, x.b[0], x.b[1]);
}
/* Example gathered from various places */
union U { float f; int i; };
void printU(int kind, const union U u)
{
switch (kind) {
case 0: printf("{f = %f}\n", u.f); break;
case 1: printf("{i = %d}\n", u.i); break;
}
}
struct list { char * value; struct list * next; };
void printlist(struct list * l)
{
for (; l != NULL; l = l->next) printf("\"%s\", ", l->value);
printf("NULL\n");
}
void printintref(int * p)
{
printf("%d\n", *p);
}
struct S { int n; int *p; };
void printS(struct S s)
{
printf("{ n = %d, p -> {%d,%d,%d,%d} }\n",
s.n, s.p[0], s.p[1], s.p[2], s.p[3]);
}
void test3(void)
{
printU(0, (const union U){0.25});
printU(1, (const union U){.i = 11});
printf("1 + 3 = %d\n", (int){1} + (int){3});
for (int i = 0; i < 3; i++) printpoint((struct point){i,i});
printpoint((struct point){1});
printpoint((struct point){.y=2});
printlist(&((struct list){"first", &((struct list){"second", NULL})}));
printintref(&((int){77}));
struct S s = (struct S) {3, (int[4]){0,1,2}};
printS(s);
printS((struct S) {4, (int[]){0,1,2,3}});
}
int main(void)
{
test1(42);
test2(12);
test3();
return 0;
}
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