Re: Renaming Lua modules (was Re: Modules with standalone main program)

[Sean Conner <sean@...>]

It was thus said that the Great Soni They/Them L. once stated:
> On 2018-02-25 04:51 PM, Sean Conner wrote:
> 
> Are there cases of static linking where you can't just change the symbol 
> names?

  Well, you can change the name in the source code (more portable, probably
the "easiest" way).  Changing the name after you have object code is ... I
don't know.  If you can, it's most likely very system dependent.  

> >   It does appear that Lua 5.3 also passes in the path (as the second Lua
> >parameter) to each searcher, so either the documenation is wrong, or it's
> >an undocumted feature.
> 
> $ lua
> Lua 5.3.4  Copyright (C) 1994-2017 Lua.org, PUC-Rio
> > package.preload.hello = print
> > require "hello"
> hello    nil

  And if you read the entire section you would see this behavior documented. 
I didn't quote the entire section (I apologize if I gave the impression I
did).

> true
> > io.open("world.lua", "w"):write("print (...)"):close()
> true
> > require "world"
> world    ./world.lua
> true
> > -- can't test a C module here but w/e, what happens if you print the 
> C stack from a C module?

  I'll assume you mean the Lua stack from a C lua function.  So here you go:

	#include <stdio.h>
	#include <lua.h>
	#include <lauxlib.h>
	
	int luaopen_cmod(lua_State *L)
	{
	  int max = lua_gettop(L);
	  int i;
	
	  for (i = 1 ; i <= max ; i++)
	  {
	    char const *name;
	    char const *type;
	    int         ri;
	
	    lua_getglobal(L,"tostring");
	    lua_pushvalue(L,i);
	    lua_call(L,1,1);
	
	    name = lua_tostring(L,-1);
	    type = luaL_typename(L,i);
	    ri   = i - max - 1;
	
	    printf("Stack: %d %d - %s %s\n",i,ri,type,name);
	    lua_pop(L,1);
	  }
	
	  lua_pushboolean(L,1);
	  return 1;
	}

	[spc]lucy:/tmp>lua-53 
	Lua 5.3.4  Copyright (C) 1994-2017 Lua.org, PUC-Rio
	> require "cmod"
	Stack: 1 -2 - string cmod
	Stack: 2 -1 - string ./cmod.so
	true
	> 

  Answers your question?

  -spc