#include <stddef.h>
#include <stdint.h>

// common types
typedef uintptr_t U;
typedef intptr_t I;

typedef uint8_t U8;
typedef uint32_t U32;
typedef int32_t I32;
typedef size_t Z;

// objects
typedef uintptr_t O;

// cons pair
typedef struct C C;
struct C {
  O head, tail;
};

// symbol
typedef struct S S;
struct S {
  U8 *data;
  U32 hash;
  Z len;
};

// symbol table
typedef struct St St;
struct St {
  I count;
  Z capacity;
  S **data;
};

// gc header
typedef struct H H;
struct H {
  I type;
  Z len;
};

// heap
typedef struct E E;
struct E {
  struct {
    U8 *start, *end;
    U8 *free;
  } from, to;

  I root_count;
  Z root_capacity;
  O **roots;
};

extern E heap;
extern St syms;

S *intern(const char *str, I len);