# lexical-scope

detect global and local lexical identifiers from javascript source code

[![browser support](http://ci.testling.com/substack/lexical-scope.png)](http://ci.testling.com/substack/lexical-scope)

[![build status](https://secure.travis-ci.org/substack/lexical-scope.png)](http://travis-ci.org/substack/lexical-scope)

# example

``` js
var detect = require('lexical-scope');
var fs = require('fs');
var src = fs.readFileSync(__dirname + '/src.js');

var scope = detect(src);
console.dir(scope);
```

input:

```
var x = 5;
var y = 3, z = 2;

w.foo();
w = 2;

RAWR=444;
RAWR.foo();

BLARG=3;

foo(function () {
    var BAR = 3;
    process.nextTick(function (ZZZZZZZZZZZZ) {
        console.log('beep boop');
        var xyz = 4;
        x += 10;
        x.zzzzzz;
        ZZZ=6;
    });
    function doom () {
    }
    ZZZ.foo();

});

console.log(xyz);
```

output:

```
$ node example/detect.js
{ locals: 
   { '': [ 'x', 'y', 'z' ],
     'body.7.arguments.0': [ 'BAR', 'doom' ],
     'body.7.arguments.0.body.1.arguments.0': [ 'xyz' ],
     'body.7.arguments.0.body.2': [] },
  globals: 
   { implicit: [ 'w', 'foo', 'process', 'console', 'xyz' ],
     exported: [ 'w', 'RAWR', 'BLARG', 'ZZZ' ] } }
```

# methods

``` js
var detect = require('lexical-scope')
```

## var scope = detect(src)

Return a `scope` structure from a javascript source string `src`.

`scope.locals` maps scope name keys to an array of local variable names declared
with `var`. The key name `''` refers to the top-level scope.

`scope.globals.implicit` contains the global variable names that are expected to
already exist in the environment by the script.

`scope.globals.explicit` contains the global variable names that are exported by
the script.

# install

With [npm](https://npmjs.org) do:

```
npm install lexical-scope
```

# license

MIT
