Lua Source Table

wiki

Implementation Description

Some articles describing the implementation:

• [The implementation of Lua 5.0] (see also [Lua Documentation])

Using Lua Tables Apart from Lua

Here's how to use only Lua's table implementation outside Lua.

/* tabletest.c - tested on Lua 5.1.3 */

#include "ltable.h"



#include <stdio.h>

#include <stdlib.h>

#include <assert.h>



/* Error handling */

void luaG_runerror (lua_State *L, const char *fmt, ...) {

  va_list argp;

  va_start(argp, fmt);

  vfprintf(stderr, fmt, argp);

  va_end(argp);

  exit(1);

}

void *luaM_toobig (lua_State *L) {

  luaG_runerror(L, "memory allocation error: block too big");

  return NULL;

}



/* Memory allocation */

void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {

  lua_assert((osize == 0) == (block == NULL));



  if (nsize == 0) {

    free(block);

    block = NULL;

  }

  else block = realloc(block, nsize);



  if (block == NULL && nsize > 0)

    luaG_runerror(L, "not enough memory");

  lua_assert((nsize == 0) == (block == NULL));

  return block;

}



/* There is no global state (L) to link allocated tables to, so do nothing. */

void luaC_link (lua_State *L, GCObject *o, lu_byte tt) { }

void luaC_barrierback (lua_State *L, Table *t) { }



int main()

{

  Table * h;

  lua_State * L = NULL;

  int i;



  h = luaH_new (NULL, 0, 0);



  /* h[5] = 10 */

  setnvalue(luaH_setnum(L, h, 5), 10);

  assert(luaH_getn(h) == 0);



  /* h[1] = 2 */

  setnvalue(luaH_setnum(L, h, 1), 2);

  assert(luaH_getn(h) == 1);



  /* iterate over table keys 1..10 */

  for(i=1; i<=10; i++) {

    const TValue * v = luaH_getnum(h, i);  /* = h[i] */

    double f = nvalue(v);

    assert(f == ((i == 1) ? 2 : (i == 5) ? 10 : 0));

    assert(v != NULL || f == 0);

    printf("%d = %f\n", i, f);

  }



  luaH_free(L, h);



  printf("done\n");



  return 0;

}

Also, in lobject.c, add "#ifndef SKIP ..... #endif" around the pushstr, luaO_pushvfstring, luaO_pushfstring, and luaO_chunkid functions to avoid link errors due to extra dependencies.

Compile with

gcc -DSKIP tabletest.c ltable.c  lobject.c

--DavidManura