"名称"的存储大小未知

Waz*_*ery 20 c struct typedef forward-declaration

编译此.c源文件时出现此错误

/INIT_SOURCE_BUILD/src/names_list.c:7:错误:"名"的存储大小是未知

#include <stdio.h>
#include "list.h"

int main(){

    struct  List names;
    names->size = 3;

    struct ListElmt michael;
    struct ListElmt john;
    struct ListElmt adams;

    names->head = michael;

    michael->data = 12;
    michael->next = john;
    john->data = 14;
    john->next = adams;
    adams->data = 16;

    struct ListElmt pointer = List->head;
    for(int x = 0; x < 3 ; x++){
        printf("Iteration.%d data: %d", x, pointer->data);
        pointer->next = pointer->next->next;
    }
}
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这是这个链表的标题

#ifndef LIST_H
#define LIST_H

#include <stdio.h>

/*                                      Define linked list elements*/

typedef struct _ListElmt{

void                *data;
struct _ListElmt        *next;

} ListElmt;

/*                                      Define a structure for the list*/

typedef struct _List{

int                 size;
int                 (*match)(const void *key1, const void *key2);
void                (*destroy)(void *data);

ListElmt             *head;
ListElmt             *tail;

} List;

void list_init(List *list, void (*destroy)(void *data));

void list_destroy(List *list);

int list_ins_next(List *list, ListElmt *element, const void *data);

int list_rem_next(List *list, ListElmt *element, void **data);

int list_size(const List *list);

ListElmt *list_head(const List *list);

ListElmt *list_tail(const List *list);

int list_is_head(const ListElmt *element);

int list_is_tail(const ListElmt *element);

void *list_data(const ListElmt *element);

ListElmt *list_next(const ListElmt *element);
#endif
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nmi*_*els 37

当你typedef一个struct这样的,你不必使用struct声明时:

List names;
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代替

struct List names;
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它也不是指针,所以names->size应该是names.size.

  • +1只是一个注释,使其更清晰:`struct List`不存在.有一个`struct _List`和一个typedef`List`,它们标识了与`struct _List`相同的类型.*(我讨厌typedef!)* (4认同)