在redis.h
中,skipnode 定义如下:
typedef struct zskiplistNode {
robj *obj;
double score;
struct zskiplistNode *backward;
struct zskiplistLevel {
struct zskiplistNode *forward;
unsigned int span;
} level[];
} zskiplistNode;
varspan
是什么意思?这个 var 存储什么?