Re: need help: some features of Lua don't fit well together

[Aapo Talvensaari <aapo.talvensaari@...>]

> On 14 April 2015 at 18:37, Konstantin Osipov <kostja.osipov@gmail.com> wrote:

> Since there is no easy way to distinguish between a Lua map and an

> array

This question arises on this list from time to time. It would be great to know if the array is really an array.

I have used this code to detect arrays:

https://github.com/bungle/lua-resty-libcjson/blob/master/lib/resty/libcjson.lua#L52-L60

But when I look lobject.h, I can see:

typedef struct Table {

  CommonHeader;

  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */

  lu_byte lsizenode;  /* log2 of size of 'node' array */

  unsigned int sizearray;  /* size of 'array' array */

  TValue *array;  /* array part */

  Node *node;

  Node *lastfree;  /* any free position is before this position */

  struct Table *metatable;

  GCObject *gclist;

} Table;

(http://www.lua.org/source/5.3/lobject.h.html)

So internally Lua seems make distinction between array parts and nodes. I'm not sure though if I have understood this even the slightest, so please correct me. The thing that I don't understand is that why this cannot be made available to Lua side as well?