我有以下代码,该代码无法正常工作。它可以编译,但是在执行时会引发很多警告和段错误:
#include <stdio.h>
enum output {
A,
B,
C,
D,
};
struct translation {
char *from;
enum output to;
};
struct dictionary {
struct translation *foo;
struct translation *bar;
};
enum language {
ONE,
ANOTHER,
};
struct dictionary languages[] = {
[ONE] = {
.foo = {
{"LF", A},
{"LLF", C},
{"RRF", D},
},
.bar = {
{"L", B},
},
},
[ANOTHER] = {
.foo = {
{"FF", B},
{"RRF", D},
},
.bar = {
{"LF", B},
{"R", C},
{"RR", D},
},
},
};
int main(void)
{
printf("%s\n", languages[ONE].foo[0].from);
return 0;
}
我可能是用错误的方式初始化languages
。
languages
数组,可以在其中通过language
访问不同的字典:languages[ONE]
languages[ONE].foo
那有可能吗?我在做什么错了?
使用gcc
进行编译时,我得到以下(裁剪的)输出:
asdf.c:27:17: warning: braces around scalar initializer
.foo = {
^
asdf.c:27:17: note: (near initialization for ‘languages[0].foo’)
asdf.c:28:25: warning: braces around scalar initializer
{"LF", A},
^
asdf.c:28:25: note: (near initialization for ‘languages[0].foo’)
asdf.c:28:26: warning: initialization of ‘struct translation *’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
[...]
相同的警告/注释在代码的多个部分重复。
答案 0 :(得分:3)
您可以执行以下两项操作:
struct translation *foo;
和struct translation *bar;
分配内存(您也可以使用malloc
动态分配内存)。例如:struct dictionary { struct translation foo[10]; struct translation bar[10]; };
struct dictionary languages[] = { [ONE] = { .foo = (struct translation []){ {"LF", A}, {"LLF", C}, {"RRF", D}, }, .bar = (struct translation []){ {"L", B}, }, }, [ANOTHER] = { .foo = (struct translation []){ {"FF", B}, {"RRF", D}, }, .bar = (struct translation []){ {"LF", B}, {"R", C}, {"RR", D}, }, }, };
注意
如@M.M所述,如果在运行时不会更改其值,那么在const
之前添加限定符struct dictionary
是一个好主意。
答案 1 :(得分:1)
只需分别初始化每个数组:
#include <stdio.h>
enum output
{
a
, b
, c
, d
};
struct translation
{
char const * from;
enum output to;
};
struct dictionary
{
struct translation * foo;
struct translation * bar;
};
enum language
{
one
, another
, languages_count
};
struct translation one_language_foo_translations[] =
{
{"LF" , a}
, {"LLF", c}
, {"RRF", d}
};
struct translation one_language_bar_translations[] =
{
{"L", b}
};
struct translation another_language_foo_translations[] =
{
{"FF" , b}
, {"RRF", d}
};
struct translation another_language_bar_translations[] =
{
{"LF", b}
, {"R" , c}
, {"RR", d}
};
struct dictionary languages[languages_count] =
{
{one_language_foo_translations, one_language_bar_translations}
, {another_language_foo_translations, another_language_bar_translations}
};
int main(void)
{
printf("%s\n", languages[one].foo[0].from);
return 0;
}