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#ifndef BDL_OBJECTS_H
#define BDL_OBJECTS_H
typedef enum ObjectType {
OBJ_TYPE_NIL,
OBJ_TYPE_TRUE,
OBJ_TYPE_FALSE,
OBJ_TYPE_FIXNUM,
OBJ_TYPE_SYMBOL,
OBJ_TYPE_STRING,
OBJ_TYPE_PAIR,
OBJ_TYPE_LAMBDA,
OBJ_TYPE_ERR,
} ObjectType;
struct Environment;
typedef struct Object {
ObjectType type;
bool marked;
union {
// OBJ_TYPE_FIXNUM
ssize_t fixnum;
// OBJ_TYPE_STRING
// OBJ_TYPE_SYMBOL
// struct {
// char *text;
// };
// OBJ_TYPE_PAIR
// struct {
// struct Object *car;
// struct Object *cdr;
// };
// OBJ_TYPE_LAMBDA
// struct {
// struct Object *params;
// struct Object *body;
// struct Environment *env;
// };
};
} Object;
void display(Object obj);
// Value initialization.
#define NIL_VAL ((Object){.type = OBJ_TYPE_NIL})
#define TRUE_VAL ((Object){.type = OBJ_TYPE_TRUE})
#define FALSE_VAL ((Object){.type = OBJ_TYPE_FALSE})
#define FIXNUM_VAL(VAL) ((Object){.type = OBJ_TYPE_FIXNUM, .fixnum = VAL})
#define BOOL_VAL(VAL) ((VAL) ? TRUE_VAL : FALSE_VAL)
// Value extraction.
#define AS_FIXNUM(VAL) ((VAL).fixnum)
// Type checking.
#define IS_TRUE(VAL) ((VAL).type != OBJ_TYPE_FALSE)
#define IS_FALSE(VAL) ((VAL).type == OBJ_TYPE_FALSE)
#define IS_FIXNUM(VAL) ((VAL).type == OBJ_TYPE_FIXNUM)
void
display(Object obj) {
switch (obj.type) {
case OBJ_TYPE_FIXNUM: {
printf("%zd", obj.fixnum);
} break;
case OBJ_TYPE_TRUE: {
printf("true");
} break;
case OBJ_TYPE_FALSE: {
printf("false");
} break;
case OBJ_TYPE_NIL: {
printf("()");
} break;
case OBJ_TYPE_STRING: {
// printf("\"%.*s\"", (int)array_size(obj.string), obj.string);
} break;
case OBJ_TYPE_SYMBOL: {
// printf(":%.*s", (int)array_size(obj.symbol), obj.symbol);
} break;
case OBJ_TYPE_PAIR: {
// printf("(");
// display_pair(obj);
// printf(")");
} break;
case OBJ_TYPE_LAMBDA: {
printf("#{procedure}");
} break;
case OBJ_TYPE_ERR: {
printf("#{error}");
} break;
}
return;
}
#endif // BDL_OBJECTS_H
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