A require() for 4.0
[
Date Prev][
Date Next][
Thread Prev][
Thread Next]
[
Date Index]
[
Thread Index]
- Subject: A require() for 4.0
- From: "Jay Carlson" <nop@...>
- Date: Mon, 3 Dec 2001 08:42:39 -0500
Here's a proposed module implementing 4.1's require() for 4.0. It should be
mostly compatible, although it won't refresh its internal path on change to
LUA_PATH.
Intended use:
local require = require or dofile
require "xmlrpc.lua"
and just give the absolute path to require.lua on the command line:
lua ~/require.lua -f xmlclient.lua
In fact, building a script or alias for this might be a good idea. One
alternative for bootstrapping is for your top level scripts to start:
dofile(LUA_REQUIRE or getenv("LUA_REQUIRE") or "")
and then specify LUA_REQUIRE someplace in the environment.
Note that this module adds path-searching to dofile() as well; many existing
modules specify their requirements with dofile.
BTW, my first glance at the 4.1 LUA_PATH made it look like trailing slashes
are mandatory in path elements; is this really the right thing for
user-friendliness and compatibility?
Jay
-- dofile(LUA_REQUIRE or getenv"LUA_REQUIRE" or "")
-- Suggested use:
--
-- bin/lua ~/require.lua -f yourfilename.lua
--
-- local require=require or dofile
-- require "xmlrpc.lua"
if require then return end
rawdofile = rawdofile or dofile
local Public, Private = {},{}
Require = Public
Private.default_path = {n=3; "", "/usr/local/share/lua-4.0/",
"/usr/share/lua-4.0/"}
if getenv("HOME") then
tinsert(Private.default_path, getenv("HOME").."/share/lua-4.0/")
end
function Private.init_path()
if LUA_PATH or getenv("LUA_PATH") then
local l_path = {n=0}
local s = LUA_PATH or getenv("LUA_PATH")
gsub(s, "([^;]+)", function (seg) tinsert(%l_path, seg) end)
%Public.path = l_path
else
%Public.path = %Private.default_path
end
end
Private.init_path()
Private.loaded = {}
function Private.dofile_on_path(package, path)
for i = 1,getn(path) do
local prefix = path[i]
local file = prefix..package
local r = rawdofile(file)
if r then return r end
end
return nil
end
function Public.require(package)
if %Private.loaded[package] then return end
if %Private.dofile_on_path(package, %Public.path) then
%Private.loaded[package]=1
else
error("required package not found: "..package)
end
end
function Public.dofile(file)
local r = rawdofile(file)
if r then return r end
return %Private.dofile_on_path(file, %Public.path)
end
require = Public.require
-- Delete this if all the modules you care about use require.
dofile = Public.dofile