This package has been deprecated

Author message:

Not maintained

undeclared

Undeclared.js

Given an AST ( esprima, acorn, ... ), find all undeclared identifiers and returns them as strings in a Set.

Why

Finding all undeclared identifiers could be used in a number of situations. For instance, this module will be part of another module that will automatically try to import all undeclared identifiers in a given script from a custom library.

Install

npm install undeclared

Usage

const 
    undeclared = require( "undeclared" ) ,
    esprima = require( "esprima" )
 
let identifiers = undeclared( esprima.parse("some JS code") )
// => Set { "undeclared ids"... }

example.js

$$1 to $$7 are undeclared identifiers across multiple scopes

let
    i = 42 ,
    j = $$1 + i
 
 
function funk() {
 
    var
        k = 41 ,
        g = (a,b) => a * j + $$3
 
    $$2(
        function(b,x) {
            $$4 += 1
            $$5 = ( function() {
                return function(y) { return $$7 + $$4 }
                } )()
            return x * $$6.prop1.prop2[ $$2 + 32 ] - i + $$4 + g( $$3, i )
            }
        )
    }

Analyse example

const 
    fs = require( "fs" ) ,
    esprima = require( "esprima" ) ,
    undeclared = require( "undeclared" )
 
fs.readFile(
    "test.js" ,
    (err,file) => {
        if ( !err ) {
            const 
                ast = esprima.parse( file ) ,
                identifiers = undeclared( ast )
            console.log( identifiers )
            }
        }
    )
 
// =>  output => Set { "$$1", "$$2", "$$3", "$$4", "$$5", "$$6", "$$7" }

License

MIT