how to use require?

[luoqi]

i use require like:
local xxx = require('xxx')
but,it also haven't to work.

--test.lua
function a()
ngx.print("test.lua");
end;

a();

--concat.lua
local test=require("test");

---

at the first request,it print:
test.lua

and,the next time,have nothing print;

[agentzh]

This is more like a Lua question. To understand why this happens, see http://www.lua.org/manual/5.1/manual.html#pdf-require

To quote the key sentence:

"The (require) function starts by looking into the package.loaded table to determine whether modname is already loaded. If it is, then require returns the value stored at package.loaded[modname]. Otherwise, it tries to find a loader for the module. "

That is, Lua's "require" will not re-load a module for the sake of performance.

So you're coding up Lua modules in a totally wrong way. We usually use Lua modules this way instead:

-- test.lua
module("test", package.seeall)
function a()
    print("test.lua")
end

And then in your content_by_lua_file directive's lua file:

-- concat.lua
local test = require("test")
test.a()

You will see the "test.lua" output on every request as you'd expect.

[luoqi]

thank you!!