meet "called object is not a function" error when use macro to Initialization tree data - c

Question

I want to implement the Lisp Cons type in C, so I use link list to achieve it.
At the same time, I use a lot of macros to simpilfy the data creation.
The code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* Macro Utils
*/
#define create_m(type) ((type *) malloc(sizeof(type)))
#define new_m(type, ...) ({ \
type * __t = create_m(type); \
*__t = (type){ __VA_ARGS__ }; \
__t; })
/*
* Type Define
*/
typedef struct atom Atom;
enum ATOM_TYPES;
// Cons Type
typedef Atom * Cons[2];
#define car(c) (c[0])
#define cdr(c) (c[1])
#define new_cons_m(car, cdr) ({ \
Cons * __c = create_m(Cons); \
car(__c) = car; \
cdr(__c) = cdr; })
// Id Type
typedef char * Id;
#define new_id_m(id) (strdup(id))
// Container Type
enum ATOM_TYPES {
ATOM_CONS, ATOM_ID
};
struct atom {
enum ATOM_TYPES type;
union {
Cons value_cons;
Id value_id;
void * value;
};
};
#define new_atom_m(t, ...) (new_m(Atom, .type = t, __VA_ARGS__))
#define new_atom_cons_m(car, cdr) ( \
new_atom_m(ATOM_CONS, .value_cons = new_cons_m(car, cdr)) )
#define new_atom_id_m(id) ( \
new_atom_m(ATOM_CONS, .value_id = new_id_m(id)) )
int main() {
printf("start program\n");
Atom * test = new_atom_cons_m(
new_atom_id_m("lisp"),
new_atom_cons_m(
new_atom_id_m("log"),
new_atom_id_m("say hello")
)
);
return 0;
}
And it failed to compile, with the following log:
arane.c: In function ‘main’:
arane.c:16:27: error: called object is not a function or function pointer
#define new_m(type, ...) ({ \
^
arane.c:18:18: note: in definition of macro ‘new_m’
*__t = (type){ __VA_ARGS__ }; \
^~~~~~~~~~~
arane.c:68:3: note: in expansion of macro ‘new_atom_m’
new_atom_m(ATOM_CONS, .value_cons = new_cons_m(car, cdr)) )
^~~~~~~~~~
arane.c:68:39: note: in expansion of macro ‘new_cons_m’
new_atom_m(ATOM_CONS, .value_cons = new_cons_m(car, cdr)) )
^~~~~~~~~~
arane.c:92:17: note: in expansion of macro ‘new_atom_cons_m’
Atom * test = new_atom_cons_m(
^~~~~~~~~~~~~~~
arane.c:66:29: note: in expansion of macro ‘new_m’
#define new_atom_m(t, ...) (new_m(Atom, .type = t, __VA_ARGS__))
^~~~~
arane.c:70:3: note: in expansion of macro ‘new_atom_m’
new_atom_m(ATOM_CONS, .value_id = new_id_m(id)) )
^~~~~~~~~~
arane.c:93:5: note: in expansion of macro ‘new_atom_id_m’
new_atom_id_m("lisp"),
^~~~~~~~~~~~~
...and much more errors
I think it is because there are some expressions in function call's argument list. I am seeking for some way to solve it, I use gcc7.5 to finish my work, if needed, I can upgrade it.
-----------2022-01-24-14:15-----------
The problem is solved, with some twest in code, however, I still don't really understand how it was happend.
The code changed as below:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* Macro Utils
*/
#define create_m(type) ((type *) malloc(sizeof(type)))
#define new_m(type, ...) ({ \
type * __t = create_m(type); \
*__t = (type){ __VA_ARGS__ }; \
__t; })
/*
* Type Define
*/
typedef struct atom Atom;
enum ATOM_TYPES;
// Cons Type
typedef Atom * Cons[2];
#define car(c) (c[0])
#define cdr(c) (c[1]) // deletes here
// Id Type
typedef char * Id;
#define new_id_m(id) (strdup(id))
// Container Type
enum ATOM_TYPES {
ATOM_CONS, ATOM_ID
};
struct atom {
enum ATOM_TYPES type;
union {
Cons value_cons;
Id value_id;
void * value;
};
};
#define new_atom_m(t, ...) (new_m(Atom, .type = t, __VA_ARGS__))
#define new_atom_cons_m(car, cdr) ( \
new_atom_m(ATOM_CONS, .value_cons[0] = car, .value_cons[1] = cdr) )
#define new_atom_id_m(id) ( \ // changes here
new_atom_m(ATOM_CONS, .value_id = new_id_m(id)) )
int main() {
printf("start program\n");
Atom * test = new_atom_cons_m(
new_atom_id_m("lisp"),
new_atom_cons_m(
new_atom_id_m("log"),
new_atom_id_m("say hello")
)
);
// Atom * test = new_atom_cons_m(NULL, NULL);
return 0;
}