Lambda in C11 + Generic

generic.lambda.c

#include <stdio.h>
#define fn(c) ({int _ c;_;})
#define list(c) sizeof(c)/sizeof(*c),c

#define map(LIST, CB) _Generic( (CB), int(*)(int, int, int*): map_arr, int(*)(int): map_val)(LIST, CB)
int map_val(size_t total, int *array, int (*cb)(int)) {
	for(int i = 0; i < total; i++)
		array[i] = cb(array[i]);
}
int map_arr(size_t total, int *array, int (*cb)(int, int, int*)) {
	for(int i = 0; i < total; i++)
		array[i] = cb(array[i], i, array);
}

int forEach(size_t total, int *array, int (*cb)(int)) {
	for(int i = 0; i < total; i++)
		cb(array[i]);
}
int findIndex(size_t total, int *array, int (*cb)(int)) {
	for(int i = 0; i < total; i++)
		if(cb(array[i]))return i;
	return -1;
}
int find(size_t total, int *array, int (*cb)(int)) {
	for(int i = 0, res; i < total; i++)
		if(cb(array[i]))return array[i];
	return -1;
}
int every(size_t total, int *array, int (*cb)(int)) {
	for(int i = 0, res; i < total; i++)
		if(!cb(array[i]))return 0;
	return 1;
}

int main(){
	int fibo[11] = {0,1};
	map(list(fibo), fn((int val, int idx, int*lst){ return idx > 1 ? lst[idx-1] + lst[idx-2] : lst[idx]; }));

	forEach(list(fibo), fn((int v){ printf("%d ", v); }));printf("\n");

	int is = every(list(fibo), fn((int v){ return v < 100; }));

	printf("every value < 100 ? %s\n", is ? "true":"false");

	map(list(fibo), fn((int v){ return v*v; }));

	forEach(list(fibo), fn((int v){ printf("%d ", v); }));printf("\n");

	int at = findIndex(list(fibo), fn((int v){ return v > 100; }));
	int el = find(list(fibo), fn((int v){ return v > 100; }));
	printf("v>100 (%i) at [%i]\n", el, at);

}