if (v) \
for (i = pool_get_first_index (v); \
i < vec_len (v); \
i = pool_get_next_index (v, i)) \
/** Iterate pool by index. */
if (v) \
for (i = pool_get_first_index (v); \
i < vec_len (v); \
i = pool_get_next_index (v, i)) \
/** Iterate pool by index. */