This project is no longer maintained.
NodeLua is a module to expose Lua bindings to Node.JS.
This is still a work in progress, collaborators welcome.
Requires Lua 5.1, will not work with 5.2
Lua and it's C libraries are required for this module to work.
npm install nodelua
var nodelua = require('nodelua');
These two environment variables should really only be used when there are installation problems
NODELUA_INCLUDE
- additional directory to search for lua.h in. example:NODELUA_INCLUDE=/opt/lua
NODELUA_FLAGS
- additional library flags to use. example:NODELUA_FLAGS=-llua5.1
To try and narrow down where the error is coming from try running the following commands:
$ find /usr/include /usr/local/include -name lua.h | sed s/lua.h//
/usr/include/lua5.1/
$ pkg-config --libs-only-l --silence-errors lua || pkg-config --libs-only-l --silence-errors lua5.1
-llua5.1
If instead they show nothing or an error then there are a few possible explanations:
- Lua Libraries are not installed
- This can be remedied with something like
[sudo] apt-get install liblua5.1-dev
- Lua Libraries are not in an expected location
/usr/include/
or/usr/local/include
- This can be solved by setting install time environment variables
NODELUA_INCLUDE
andNODELUA_FLAGS
NODELUA_INCLUDE="/path/where/lua.h/is/" NODELUA_FLAGS="-llua5.1" npm install nodelua
The NodeLua
module itself contains the object LuaState
as well as some constants.
var lua = new nodelua.LuaState('lua')
STATUS
is an object that contains the constants for values returned by LuaState.status()
or LuaState.statusSync()
.
nodelua.STATUS
conatins the following constants:
YIELD: 1
ERRRUN: 2
ERRSYNTAX: 3
ERRMEM: 4
ERRERR: 5
GC
is an object of constants used for controlling the lua garbage collector.
nodelua.GC
conatins the following constants:
STOP: 0
RESTART: 1
COLLECT: 2
COUNT: 3
COUNTB: 4
STEP: 5
SETPAUSE: 6
SETSTEPMUL: 7
INFO
is an object containing constants with information about the version of lua you are using.
nodelua.INFO
contains the following constants:
VERSION
VERSION_NUM
COPYRIGHT
AUTHORS
The LuaState
is an object wrapper around a lua_State
instance.
When creating a new LuaState
you must provide it with a name, this is to help stop conflicts between registering functions.
You should provide unique names to each LuaState
instance.
Returns the name provided when creating creating the LuaState
The doFile
method is used to load and execute lua code stored in file_name
.
lua.doFile('test.lua', function(error, ret_value){
if(!error && ret_value){
console.dir(ret_value);
} else{
console.error(error);
}
});
This is the synchronous version of doFile
, any value returned from the script is returned.
var ret_value = lua.doFileSync('test.lua');
console.dir(ret_value);
The doString
method is the same as doFile
except the code is loaded from lua_code
rather than from a file.
lua.doString("print('Hello, Lua')", function(error, ret_value){
if(!error && ret_value){
console.dir(ret_value);
} else{
console.error(error);
}
});
This is the synchronous version of doString
, any value returned from the script is returned.
var ret_value = lua.doString("return 5");
console.dir(ret_value);
The setGlobal
method is used to provide lua with the global variable name
containing the value value
.
lua.setGlobal('test', 'value');
The getGlobal
method is used to retrieve either a value set by setGlobal
or a global variable in any lua code that has been run.
console.log(lua.getGlobal('test'));
registerFunction
is used to expose a javascript function to lua.
lua.registerFunction('add_them', function(a, b){
return a + b;
});
var ret_value = lua.doStringSync('return add_them(2, 4)');
console.dir(ret_value);
status
will return the current status code for lua. The result can be 0
for normal or one of the error codes in nodelua.STATUS
.
lua.status(function(code){
if(code == nodelua.STATUS.ERRSYNTAX){
console.error('Lua Syntax Error');
}
});
This is the synchronous version of status
var code = lua.statusSync();
console.dir(code);
collectGarbage
is used to control the lua garbage collector. GC_CODE
should be one of the codes taken from nodelua.GC
.
lua.collectGarbage(nodelua.GC.COLLECT, function(code){
console.dir(code);
});
This is the synchronous version of collectGarbage
.
var code = lua.collectGarbageSync(nodelua.GC.COLLECT);
console.dir(code);
Push value
onto the Lua stack.
lua.push(5);
Pop num
items from the stack. Default is 1.
lua.pop(5);
Return the number of elements on the Lua stack.
var num = lua.getTop();
Set the top of the Lua stack to index
.
lua.setTop(3);
Replaces the top stack element into the specified index
lua.replace(3);
close
should be used whenever you have finished using a LuaState
. This will simply call lua_close
on the lua_State
for that object.
See ./examples/
.
var nodelua = require('nodelua');
var lua = new nodelua.LuaState('example');
lua.registerFunction('add_them', function(a, b){
return a + b;
});
lua.doFile('some_file.lua', function(error, ret_value){
console.dir(lua.getGlobal('some_var'));
});
The MIT License (MIT) Copyright (c) 2012 Brett Langdon brett@blangdon.com
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.