Hi,
that topic has been discussed on several places in the we
(stackoverflow, etc..) and while people came up with some solutions, I
haven't really seen anybody making a case against it. So I'm
wondering if that behaviour could be build into Lua ...
What exactly do I mean?
-----------------------
consider the following layout:
-basedir
\
-scripts
\
-a.lua
-b.lua
a.lua has a require('b')
Now if I do the following:
# cd basedir/scripts
# lua a.lua
everything runs smoothly. But if I
# cd basedir
# lua scripts/a.lua
I get an error that module 'b' can't be found because the searchpath
is based of the current working directory.
How to deal with it?
--------------------
Append the path of the currently executed Lua file to package.path
(temporarily)
If we add the following (slighly hackish) code to loadlib.c:
// find location of current file
static void appendcurrentpath(lua_State *L, const char *pname ) {
lua_Debug ar;
lua_getstack( L, 2, &ar ); // needs safeguarding
lua_getinfo( L, "S", &ar ); // needs safeguarding
strrchr( ar.short_src, '/' )[1] = 0x00; // cut off filename
if (0 == strncmp(pname, "cpath", 5))
lua_pushfstring(L, ";%s/?.so", ar.short_src );
if (0 == strncmp(pname, "path", 4))
lua_pushfstring(L, ";%s/?.lua;%s/?/init.lua", ar.short_src,
ar.short_src );
lua_concat(L, 2);
}
and call that function from within *findfile:
static const char *findfile (lua_State *L, const char *name,
const char *pname,
const char *dirsep) {
const char *path;
lua_getfield(L, lua_upvalueindex(1), pname);
appendcurrentpath(L, pname); // insert the call here
path = lua_tostring(L, -1);
if (path == NULL)
luaL_error(L, "'package.%s' must be a string", pname);
return searchpath(L, name, path, ".", dirsep);
}
the path off the currently executed .lua file gets temporarily
appended to path and cpath. Sure that will need some safeguarding.
Would that make sense to have it in Lua?
-Tobias
