包路径

wiki

whatever = require "whatever"       

Lua 会在很多地方尝试寻找一个名为 whatever 的包，其中大部分的名字中都包含 whatever。如果都找不到，Lua 会给出一个错误信息，列出所有尝试过的路径，类似这样：

stdin:1: module 'whatever' not found:
	no field package.preload['whatever']
	no file '/usr/local/share/lua/5.2/whatever.lua'
	no file '/usr/local/share/lua/5.2/whatever/init.lua'
	no file '/usr/local/lib/lua/5.2/whatever.lua'
	no file '/usr/local/lib/lua/5.2/whatever/init.lua'
	no file './whatever.lua'
	no file '/usr/local/lib/lua/5.2/whatever.so'
	no file '/usr/local/lib/lua/5.2/loadall.so'
	no file './whatever.so'
stack traceback:
	[C]: in function 'require'
	stdin:1: in main chunk
	[C]: in ?

这个列表的示意性表示保存在变量 package.path 中。对于上面的列表，该变量包含：

/usr/local/share/lua/5.2/?.lua;/usr/local/share/lua/5.2/?/init.lua;/usr/local/lib/lua/5.2/?.lua;/usr/local/lib/lua/5.2/?/init.lua;./?.lua